Grade 2 Teacher's Edition - Chapters 1-6

TM M A T HFOR ATHEMATICAL BILITIES & HINKING ABITS A UNIQUE SYSTEM THAT CHANGES THE FOCUS FROM ROTE PRACTICE TO REAL MATH WISDOMTeacher’s Edition Second Grade



SPOTS MATH Grade 2 Teacher’s Booklet Chapter 1 IntroductionThis chapter sets a foundation for the students’learning through the rest of theyear. The computational strategies, models and problem-solving constructsapplied in this chapter (many of which were first introduced in first grade) willbe extended throughout the second-grade program.The chapter opens with a review of addition and subtraction with numbers upto 10. Dot Cards are utilized as a tactile/visual model. Two distinct subtractionstrategies are reviewed in this chapter. Modeling these basic problems earlyon will help solidify students’ recall of these facts.In Lesson 5 of this chapter, students continue their work with sums anddifferences by exploring number-fact families. In this section, students arefamiliarized with the concepts of part and whole, and the idea that two partsadd up to a whole or that one part can be subtracted to find the other part.The math-puzzle model and number-sentence format that are used to explorebasic facts are then extended to finding an unknown number and, finally, tofinding an unknown number in word problems. New for second grade is theuse of a box ( ) to represent the unknown number in all positions, whetherthe unknown number is the sum, difference, addend, minuend or subtrahend.This box replaces the question mark (?) used in kindergarten and first grade;it allows for students to go back and check their work in the context of theoriginal problem setup. The process of analyzing a solution is an importantlifelong problem-solving skill, to which students will begin to gain exposurethrough their mathematical work here.Adding to form teen sums and subtracting from a teen number are other skillsaddressed in this chapter. Using Dot Cards and number lines to explore how toadd or subtract to get ten, and then to add or subtract the rest, turns this studyinto more than just a monotonous fact drill, by allowing students to apply avariety of strategies to arrive at the solution to a problem.Chapter 1 sets the stage for an exciting year of growth in mathematical andproblem-solving skills for your students. Happy learning! *Note: Students will continue to practice with addition and subtraction facts upto 20, using the My Math Facts practice sheets.

Chapter 1 Lesson 1: Adding Through Ten INTRODUCTORY STATEMENT: II. Adding with Dot Cards Today we will begin to review some of what Write 4 + 2 = ___ on the board. Ask a student to tell you how you learned in the first grade. to show it with Dot Cards (by placing two white counters on Dot Card-4). Ask how many there are in all, and fill in the sum. GOAL: Read the equation together. Students will review addition facts to ten. Do the same for 5 + 3, 8 + 2, and 6 + 3. MATERIALS NEEDED: pretzels or other snack, Dot Cards and counters Write 5 + 2 on the board, and place Dot Card-5 next to it. Say: Now let’s solve this without adding on the counters. Let’sCommon Core Standard: CCSS2.OA.2 pretend to add on two white counters. We begin with 5, and we add on 6 and 7. There are 7 in all. LESSON WARM-UP Do the same with 4 + 3 and 6 + 4. Together, pretend to add Review facts for fluency using the My Math Facts counters and solve the equation. practice booklet. III. Adding by counting on THINKING TRIGGER Write 7 + 2 = ___ on the board. Say: Let’s try this without Dot Cards. Let’s solve this by counting on. We begin with the larger number – 7, and we count on 8 and 9. We have 9 in all. [Fill in the sum.] Repeat with 3 + 2, 5 + 4, and 7 + 3. What is the “math way” to show that we are putting two IV. Doubles facts groups together? Write these doubles facts on the board: 3 + 3, 5 + 5, and 4 +CONCEPT DEVELOPMENT 4. Ask: What is special about these facts? [both addends are the same] What do we call these facts? [doubles facts] [Find theI. The concept of adding sums.]Pass out ten pretzels, or ten of some other snack, to each STUDENT TEACHERstudent. Have the students make a group of seven pretzelsand another group of three pretzels. Now put the groups Write some other addition equations (sums up to 10) ontogether. Ask: What number sentence can we write to show the board. Have a volunteer choose an equation and tellwhat we just did? [7 + 3 =10] a story problem for it. Have another volunteer solve the problem. Discuss the ways they found the sums. Did theyRepeat with the equation 6 + 4 = ___. add by counting on? By using doubles facts? Repeat for each equation.Identify the parts of the number sentence: Addend plusaddend equals the sum. Explain that addends are the parts, Copyright © by SPOTS Educational Resources. All rights reserved.plus means putting the numbers together, and sum meanshow many there are in all.In the same way, have the students make groups of fivepretzels, combine the groups, and then write the numbersentence on the board.2

Using the Book: pages 3-4 Fill in the addition number sentence. Addition Through Ten Write the number sentence and solve. 1. 2. 3. 1. Tamara has 5 fuzzy stickers. She gets 2 shiny stickers as a reward. 4 + 4 = 8 6 + 2 =8 5 + 4 = 9 How many stickers does she have in all? Add. Circle the doubles facts. Number sentence: 5 + 2 = 7 Tamara has 7 stickers in all. 4. 6 5. 7 6. 4 7. 5 8. 7 +2 +3 +2 +4 +2 2. For snack, Benny has 6 slices of apple 8 10 6 9 9 and 3 slices of banana. How many slices of fruit does Benny have? 9. 5 10. 3 11. 6 12. 4 13. 6 +5 +3 +4 +3 +3 Number sentence: 6 + 3 = 9 10 6 10 7 9 Benny has 9 slices of fruit. 14. 4 15. 7 16. 5 17. 2 18. 9 3. 8 cats sit near a tree. +4 +0 +3 +2 +1 2 more cats come to sit there. 8 7 8 4 10 How many cats are near the tree? 8 Number sentence: 8 + 2 = 10 There are 10 cats near the tree. Chapter 1 Lesson 1 OA.2 Addition Through Ten 3 4. Mike has 4 goldfish. Bill has 3 more goldfish than Mike. How many goldfish does Bill have? Number sentence: 4 + 3 = 7 Bill has 7 goldfish. 4 Now let’s practice adding with numbers to ten. Remember can use Dot Cards, add by counting on, or use doubles facts. some of the ways you can add two numbers together. You DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Some students may need to review their basic facts. Have What did we learn today in math class? students practice together in pairs, using Addition Dot Today we reviewed adding to ten. Cards 1-9. Tomorrow we will practice this more.Copyright © by SPOTS Educational Resources. All rights reserved. 3

Chapter 1 Lesson 2: Practice: Addition Through Ten INTRODUCTORY STATEMENT: II. Applying the skill Copyright © by SPOTS Educational Resources. All rights reserved. Yesterday we reviewed adding to ten. Today we willpractice that. We will discuss adding in any order. We Write 3 + 5 and 5 + 3 on the board. Say: Both of these addition sentences have the same numbers. Will they have the same sum will also practice different ways to make ten. or different sums? [the same sum] Why? [We can add in any order and get the same sum.] [Solve 5 + 3.] We know that 5 + GOAL: 3 = 8. We also know that 3 + 5 = 8. Students will apply the commutative property of Write 2 + 8 on the board. Say: The first addend, 2, is less than addition. the second addend, 8. Which number sentence is easier to solve Students will find combinations of numbers that equal by counting on: 2 + 8 or 8 + 2? Why? [8 + 2, because we would ten. only have to count on from 8: 9, 10!] We can switch the order MATERIALS NEEDED: ten pennies and a cup for each of the addends, because it doesn’t matter which addend comes student first and which addend comes second. [Write 8 + 2 = ___.] What is the sum? [10] What is the sum of 2 + 8? [also 10]Common Core Standard: CCSS2.OA.2 Draw two columns on the board. In the left-hand column, LESSON WARM-UP place three cards with the number sentences 2 + 7 = ___, 3 + 5 = ___, and 4 + 6 = ___. In the right-hand column, place Review facts for fluency using the My Math Facts three cards with the number sentences 5 + 3 = ___, 6 + 4 = practice booklet. ___, and 7 + 2 = ___. Say: Let’s look at the first number sentence: 2 + 7. When we add, we start with the greater number. Which THINKING TRIGGER addend is greater? [the second] Let’s find the matching number sentence on the other side of the board. [Place the 7 + 2 = ___ Write 3 + 7 on the board. Ask the students to tell how they card next to the 2 + 7 = ___ card, and solve both equations.] would solve it. Continue in the same way with 3 + 5 and 4 + 6.CONCEPT DEVELOPMENT III. Finding combinations of tenI. Adding in any order Hand out ten pennies and a cup to each student. Have theAsk four students with black hair (or some other easily students shake their pennies in the cup and then pour themidentifiable feature) and two students with brown hair to out. Ask them to sort the pennies according to how they fell:stand in front of the class. Have the black-haired students heads in one section and tails in another. Draw a T-chart andstand to the right. With the class, write a number sentence to label it “Ways to Make Ten.” Label the columns “Heads” andshow how many they are altogether (4 + 2 = 6). “Tails.” Ask students to tell how many of their pennies landedAsk the groups to switch places so that the brown-haired on heads and how many on tails. Write the combinations ongroup is at the right. Write another number sentence to show the chart until all the possibilities have been displayed.how many there are now (2 + 4 = 6). Ask: Does the order inwhich these students are standing change how many there are Write 8 + ___ = 10. Ask: If 8 pennies fell on heads, how many fellat the front of the class? [No; there are still six students.] When on tails? [2] [Repeat with 6 + ___ = 10 and 5 + ___ = 10.]we add groups, or numbers, we can add them in any order andget the same sum. STUDENT TEACHERRepeat this with another two groups of students. Write six equations on the board: three with a greater first addend and three with a greater second addend. For each one, ask a student to complete the equation by finding the sum and to explain the thinking process he/she used. Ask: Which way was an easier or faster way to add? [Elicit that when we put the greater addend first, it is easier to count on and get the answer.]4

Using the Book: pages 5-6 Practice: Addition Through Ten Draw a line to the crayon that shows When we add, we think of There are different ways the matching number sentence. the greater number first! to make a sum of ten. Fill in the sums. Fill in the missing addend to complete the number sentence. 1. 3 + 7 = 10 6+2= 8 1. 8 + 2 = 10 2. 5 + 5 = 10 3. 7 + 3 = 10 2. 2 + 6 = 8 5+3= 8 4. 10 + 0 = 10 5. 6 + 4 = 10 6. 9 + 1 = 10 3. 3 + 4 = 7 7 + 3 = 10 Add. Think of the greater addend first. 4. 3 + 5 = 8 4+3= 7 7. 3 + 5 = 8 8. 2+4= 6 9. 4 + 5 = 9 10. 0 + 7 = 7 11. 6+3= 9 12. 3 + 7 = 10 Add. 8. 4 + 5 = 9 13. 3 + 4 = 7 14. 1+6= 7 15. 2 + 5 = 7 16. 6 + 4 = 10 17. 2+7= 9 18. 2 + 6 = 8 5. 1 + 4 = 5 9. 3 + 5 = 8 6. 2 + 4 = 6 10. 1 + 5 = 6 LET’S WRITE! 7. 3 + 4 = 7 14. 2 + 7 = 9 11. 4 + 6 = 10 How does knowing how to solve 7 + 3 help you solve 3 + 7? 15. 3 + 7 = 10 The addends are the same. Changing the order does not change 12. 2 + 6 = 8 the sum. So, 7 + 3 = 3 + 7. 13. 3 + 6 = 9 16. 1+7= 8 5 6 Chapter 1 Lesson 2 OA.2 Practice: Addition Through Ten writing. Read the question and discuss it with the class. In- vite some students to describe their thinking process. Then Now let’s practice adding with numbers to ten. Remember, explain the task: Each student is to think about the question when you add you can start with the greater number first, and write his/her answer on the lines in the book. then count on, make ten, or think of an addition fact you know. Ask some students to share their writing with the class. Refer the students to the Let’s Write section on page 6. This is new to them. They will explain their thinking byCopyright © by SPOTS Educational Resources. All rights reserved. DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: When using the addition strategy of “counting on,” some What did we learn today in math class? students may include the beginning number with the Today we reviewed more addition through ten. number they counted on. Suggest that students circle the greater number and count on from there, or they can Tomorrow we will review subtraction. write the numbers they counted on above the second addend. 5

Chapter 1 Lesson 3: Subtraction Through Ten INTRODUCTORY STATEMENT: subtracting a little? [from the top] Let’s do that together. [As We’ve reviewed addition through ten. Today we you cross off the dots, count back together:] We cross off the 9, 8, and 7. There are 6 left. 9 − 3 = 6. will review subtraction through ten. Repeat with 10 − 2, 7 − 3, and 9 − 4. (Note: When counting GOAL: back, be sure to count the dots you are crossing off; thus, for 10 − 2, count back the 10 and the 9, and point out that we are left with 8.). Students will subtract from numbers through ten. III. Counting back to subtract without MATERIALS NEEDED: No materials are needed for Dot Cards this lesson. On the board write 7 − 2 = ___. Say: Now let’s subtract byCommon Core Standard: CCSS2.OA.2 counting back without using Dot Cards. Let’s imagine we have LESSON WARM-UP Dot Card-7, and we are crossing off the 7 and the 6. We are left Review facts for fluency using the My Math Facts with…? [5] practice booklet. Repeat with 8 − 3, 10 − 2, and 9 – 3. Point out that we always THINKING TRIGGER start counting back from the number we have, just as we do on the Dot Cards. On the board, write 6 − 2 = ___. Ask if the answer will be more or less than 6, and why. IV. Subtracting a lot Write 10 − 8 = ___, and place Dot Card-10 on the board. Ask: Are we taking away a little or a lot? [a lot] Who remembers how we subtract a lot? [We cross off the dots from the bottom with one big X, and count on to see how many are left.] Let’s do that. [Cross off the eight dots, and count on together:] 9, 10. There are two left. 10 − 8 = 2. Repeat with 8 − 5, 9 − 7, and 10 – 6.CONCEPT DEVELOPMENT V. Counting on to subtract without using Copyright © by SPOTS Educational Resources. All rights reserved. Dot CardsI. The concept of subtraction Write 8 − 6 = ___ on the board, and say: Now let’s do this oneWrite 7 − 2 = ___ on the board. Have the class read the mentally. Are we subtracting a little or a lot? [a lot] How do weequation together. Circle the minus sign and ask what it tells do that? [We cross off 6 from the bottom, and count on.] Let’sus (it tells us to take away). imagine doing that, and count on together: We cross off 6. We have dots 7 and 8 left. There are 2 left. 8 − 6 = 2.Tell a story problem for the equation: I had 7 potatoes. I atetwo for supper. How many are left? [5] STUDENT TEACHERGive two other subtraction scenarios and two or three Place Dot Cards 5, 6, 7, and 8 on the board. For each one,different subtraction equations. Example: I had stickers and I have students write a subtraction number sentence on theirgave some away. Have students match up each scenario with papers. Ask volunteers to write their number sentences onthe appropriate math problems (e.g., I had and 5 stickers and the board, and ask other volunteers to solve them by cross-gave 2 away…matches with 5 − 2 = 3) ing off dots and filling in the differences. Ask: How did you decide from what part of the Dot Card to cross off the dots?II. Subtracting a little [Elicit that when students are subtracting “a lot” relative to the first number (the minuend), then they might prefer toWrite 9 − 3, and place Dot Card-9 on the board. Ask: Are wetaking away a little or a lot? [a little] Who remembers fromwhat part of the Dot Card we cross off the dots when we are6

Using the Book: pages 7-8 When we subtract a little, Subtraction Through Ten When we subtract a lot, we cross off 10 – 7 = 3 we cross off the dots from the dots from the bottom and count the top as we count back. 10 – 2 = 8 4. We cross off the 10 and 9. on to see how much is left. There are 8 left. We cross off 7. We are left with 8, 9, and 10. There are 3 left. Cross off the dots you need to subtract. 4. Write the difference. Cross off the dots you need to subtract. 1. 2. 3. Write the difference. 1. 2. 3. 6–2= 4 9–3= 6 9–4= 5 8–3= 5 9 – 7 = 2 10 – 6 = 4 6 – 5 = 1 8 – 6 = 2 5. 6. 7. 8. 5. 6. 7. 8. 5 – 2 = 3 10 – 3 = 7 10 – 4 = 6 7 – 2 = 5 7–4= 3 9 – 5 = 4 9 – 6 = 3 10 – 9 = 1 Subtract. 10. 11. 12. Subtract. 10. 11. 12. 9. 9. 6–1= 5 7–3= 4 9–2= 7 8–7= 1 6–4= 2 9–8= 1 10 – 2 = 8 10 – 5 = 5 14. 15. 16. 13. 14. 15. 16. 13. 4–3= 1 10 – 8 = 2 8 – 4 = 4 5–1= 4 8–2= 6 4–0= 4 7–1= 6 5–5= 0 Chapter 1 Lesson 3 OA.2 Subtraction Through Ten 7 8 Now let’s practice subtracting numbers to ten. Remember subtracting a lot, you cross off dots from the bottom of the that when subtracting a small amount, you cross off dots Dot Card and count on to find the difference. from the top of the Dot Card as you count back. When cross off from the bottom of the card. This skill is similar to DIFFERENTIATED INSTRUCTION “counting on” to get the difference. On the other hand, if students are subtracting “a little” relative to the first number, Give students several subtraction number sentences, they may prefer to cross off dots from the top. This skill is such as 9 − 6 = ___ and 8 − 3 = ___. Have them tell similar to “counting back” to get the difference. whether they are subtracting a little or a lot and, there- fore, how they will subtract. Lead them to understandCopyright © by SPOTS Educational Resources. All rights reserved. that when subtracting a little, they should cross off dots from the top as they count back. When subtracting a lot, they should cross off dots from the bottom and count on. CLOSING STATEMENT: What did we learn today in math class? Today we reviewed subtracting from numbers up to 10. Tomorrow we will practice more. 7

Chapter 1 Lesson 4: Practice: Subtraction Through Ten INTRODUCTORY STATEMENT: II. Review and connect to subtracting without Yesterday we reviewed subtraction through ten. Dot Cards Today we will practice subtraction through ten. Write 7 − 6 and 7 − 3. Say: Now let’s do these in our heads. GOAL: [Point to 7 − 6.] Are we subtracting a little or a lot? [a lot] How do we do that? [Cross off 6 from the bottom, and count on.] Students will practice subtraction from numbers Let’s imagine doing that, and let’s count on together: We cross through ten. off 6. We have 7. There is 1 left. 7 − 6 = 1. MATERIALS NEEDED: No materials are needed for this lesson. Point to 7 − 3 and ask: Are we subtracting a little or a lot? [a little] How do we subtract a little? [We count back as we cross off dots from the top.] Let’s imagine crossing off dots as we count back. We cross off the 7, 6, and 5. There are 4 left. 7 − 3 = 4.Common Core Standard: CCSS2.OA.2 STUDENT TEACHER LESSON WARM-UP Write 8 − 3, 6 − 1, 10 − 7, and 9 − 7 on the board. For each equation, ask students to tell you whether you Review facts for fluency using the My Math Facts are subtracting a little or a lot, and solve accordingly. practice booklet. THINKING TRIGGER Copyright © by SPOTS Educational Resources. All rights reserved. On the board, write 5 − 3. Ask: How would you find the difference – by counting back or by counting on? [Either way is correct.]CONCEPT DEVELOPMENTI. Compare subtracting a lot with subtracting a littleWrite 8 − 2 = ___ and 8 − 5 = ___, and place Dot Board-8 onthe board. Point to 8 − 2 and ask: Are we subtracting a littleor a lot? [a little] How do we subtract a little? [We count backas we cross off dots from the top.] [As you cross off the dots,count back together.] We cross off the 8 and the 7. There are 6left. 8 − 2 = 6. [Erase the X from the Dot Board.]Now refer to 8 − 5, and ask how to solve it. Ask: Are wesubtracting a little or a lot? [a lot] How do we subtract a lot?[We cross off the dots from the bottom with one big X, thenwe count on to see how many are left.] [Cross off the fivedots, and count on together:] 6, 7, and 8. There are three left.8 − 5 = 3.8

Using the Book: pages 9-10 Practice: Subtraction Through Ten Decide if you are subtracting a lot or a little. 4. Subtract. 2. 7 3. 6 4. 9 5. 10 6. 4 Cross off the dots you need to subtract. –5 –2 –8 –3 –0 Write the difference. 1. 10 2 4 1 7 4 –6 1. 2. 3. 4 9–7= 2 9–3= 6 8–2= 6 8–5= 3 7. 5 8. 9 9. 6 10. 8 11. 7 12. 4 –4 –3 –3 –5 –3 –2 5. 6. 7. 8. 1 6 3 3 4 2 10 – 4 = 6 10 – 8 = 2 8 – 7 = 1 8 – 3 = 5 13. 10 14. 8 15. 7 16. 6 17. 9 18. 8 –5 –4 –4 –6 –5 –6 9. 10. 11. 12. 5 4 3 0 4 2 9–6= 3 9–4= 5 7–6= 1 7–2= 5 Write the number sentence and solve. 19. Nan has 10 markers. 13. 14. 15. 16. Lizzy has 3 fewer markers than Nan. 8–1= 7 8–6= 2 5–4= 1 5–2= 3 How many markers does Lizzy have? Chapter 1 Lesson 4 OA.2 Practice: Subtraction Through Ten 9 Number sentence: 10 – 3 = 7 Lizzy has 7 markers. LET’S WRITE! Look at exercise number 18. Explain how you solved 8 – 6. Answers will vary. Sample answer: I thought of Dot Card - 8 and imagined crossing off 6 dots from the bottom. I was left with 2. 10 Now let’s practice subtracting numbers to ten. When we discuss it. Have the students write the number sentence and subtract a little, we cross off from the top as we count the difference on their own. back. When we subtract a lot, we cross off from the bottom and count on. [Point out that on page 10 they will solve Remind the students that they encountered a Let’s Write! examples 1 through 18 “in their heads.” problem in a previous lesson, and that in this section they will explain their thinking by writing. Refer the class to the story problem, read it together, andCopyright © by SPOTS Educational Resources. All rights reserved. DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Give students several subtraction number sentences, What did we learn today in math class? such as 9 − 6 = ___ and 8 − 3 = ___. Have them tell if they Today we practiced subtracting from numbers to ten. are subtracting a little or a lot, and therefore, how they will subtract. Lead them to understand that when sub- Tomorrow we will talk about number families. tracting a little, they should cross off dots from the top as they count back. When subtracting a lot, they should cross off dots from the bottom and count on. 9

Chapter 1 Lesson 5: Number Families INTRODUCTORY STATEMENT: Have the students demonstrate each story with their crayons So far we’ve practiced adding and subtracting. and suggest the matching number sentence. Write the equations on the board. Today we will talk about number families. You should have four equations: 5 + 3 = 8, 3 + 5 = 8, 8 − 3 GOAL: = 5, 8 − 5 = 3. Refer to the equations and say: These number sentences are like a family. They all use the same numbers. The Students will understand the relationship between two parts form the whole, and when we start with the whole, we addition and subtraction. can take away either part and we’re left with the other part. We MATERIALS NEEDED: magnetic math puzzles; can call these numbers a family – a number family. crayons; index cards II. Practicing with number familiesCommon Core Standard: CCSS2.OA.2 Place or draw a math puzzle on the board, and fill it in with LESSON WARM-UP the numbers 9, 6, and 3. Under the puzzle draw four number- sentence formats (two for addition and two for subtraction). Review facts for fluency using the My Math Facts Say: Let’s see which number sentences we can make with these practice booklet. numbers. When we add we begin with the parts, the two smaller numbers. We add them together and end up with a whole. THINKING TRIGGER Which number can we use for the first number in the addition sentence? [one of the parts: 6 or 3] Which number should we What is a family? What do you think a number family is? use for the second number in the addition sentence? [the other [Accept all relevant suggestions.] part] Which number is the sum? [the whole: 9] [Fill in the equation. Repeat for the second addition equation.]CONCEPT DEVELOPMENT In the same way, fill in the two subtraction equations. Say:I. Introducing number families using When we subtract, we begin with the whole – the largest manipulatives number. When we take away either part, the other part is the difference. Which number should we use for the first number inDraw or place a math puzzle on the board and review the the subtraction sentence? [the whole: 9] Which number can weparts of the puzzle (part, part, whole). Fill it in with the use for the second number in the subtraction sentence? [one ofnumbers 8, 5, and 3. Say: We will use crayons to show stories the parts: 6 or 3] Which number is the difference? [the otherwith these numbers. Whazt is our whole number? [8] So we will part] [Fill in the equation. Repeat for the second subtractionuse eight crayons in all. [Point to the parts of the puzzle and equation.] These numbers are a family – a number family.say:] These are the parts. We will divide the eight crayons intotwo groups: a group of …? [5] and a group of …? [3] [Have the Repeat this process with the numbers 5, 4, and 1. Begin withstudents use their crayons to make the groups.] a math puzzle filled in with these numbers, and then guideElicit stories that tell about the combination of these the students to tell what the four equations are.numbers. (For example: I have three crayons on my desk andfive crayons in my pencil case. How many crayons do I have in Copyright © by SPOTS Educational Resources. All rights reserved.all?) Remind the class that we can put together the two parts,and we can also take away a part.10

Using the Book: pages 11-12 Number Families Fill in the numbers in the math puzzle. The Numbers in a Math Puzzle Are a Family Write two number sentences for each math puzzle. When we add, we begin with a part. 1. 2 4 6 2. 6 8 2 3. 9 4 5 When we subtract, we begin with the whole. Complete each math puzzle. 9 6 8 9 Write four number sentences for each math puzzle. 1. 2. Whole Whole Whole Whole Whole 24 62 45 Part Part Part Part Part Part 6 3 2+ 4 =6 6 + 2 =8 4+5 =9 Part Part Part Part Whole Part Part Whole Part Part Whole Part Part 6+ 3 =9 6– 2 =4 8 – 2=6 9–5 = 4 Whole Whole Part Part Whole Part Part Whole Part Part + =7 Part Part Whole =9 Part Part 3+ 6 Whole 4. 8 3 5 5. 4 10 6 6. 5 2 3 =7 + Whole Part Part =3 Part Part Part =5 9– 6 8 10 5 Part =6 – Whole Part Part Whole Whole Whole =2 Whole Part Part 9– 3 35 64 23 – Whole Part Part Part Part Part Part Part Whole Part 5+ 3= 8 6 + 4 = 10 3+ 2=5 3. 4. 7 Part Part Whole Part Part Whole Part Part Whole 5 Whole Whole 14 43 8 –5=3 10 – 6 = 4 5 –3= 2 Whole Part Part Whole Part Part Whole Part Part Part Part Part Part 4+1=5 4+3 = 7 LET’S WRITE! Part Part Whole Part Part Whole Look at number 6. How did you decide which number was the whole and which 1+4=5 3+4 = 7 numbers were the parts? I picked the largest number -5- as the whole and the two Part Part Whole Part Part Whole smaller numbers 2 and 3 as the parts. Because 2 + 3 = 5. 5 –4=1 7–4 = 3 Whole Part Part Whole Part Part 5 –1=4 7–3 = 4 Whole Part Part Whole Part Part Chapter 1 Lesson 5 OA.2 Number Families 11 12 Now let’s practice working with number families. On page whole, while the smaller numbers are the parts that make up 12, you need to use the numbers given to fill in the math that whole. puzzles. Remember that the largest number is always theCopyright © by SPOTS Educational Resources. All rights reserved. STUDENT TEACHER DIFFERENTIATED INSTRUCTION Divide the class into pairs. Give each student three index Some students may need suppport in understanding cards with a set of three numbers written across each. what “a part” means in the context of number families. Include some sets that are number families and some sets Use manipulatives, such as 3 black counters and 4 white that are not. Have students use at least two equations to de- counters. Discuss that the whole group of 7 counters termine which sets are number families and which are not is made up of two parts: 3 black counters and 4 white number families. Select volunteeers to demonstrate how counters. they determined whether or not a set is a number family. Make sure to emphasize responses that indicate that in a CLOSING STATEMENT: number family, when you add the two smaller numbers to- What did we learn today in math class? gether you get the largest number, and when you subtract Today we learned about number families – numbers one of the smaller numbers from the largest number you that belong together. Tomorrow we will find two get the other smaller number. unknown addends to solve story problems. 11

Chapter 1 Lesson 6: Problem Solving: Both Addends Unknown INTRODUCTORY STATEMENT: On the board, draw a math puzzle and fill it in with the Yesterday we reviewed number families. words Whole, Part, and Part, as explained in the previous Today we will find two unknown addends to lesson. Also, label the top section “All blocks,” the left side “Red blocks,” and the right side “Yellow blocks.” Alongside the solve story problems. puzzle, draw a reversed blank number sentence format: ___ = ___ + ___. In the puzzle, fill in 4 as the whole and write GOAL: in 3 as one part and 1 as the other part. Say: This could be one way to make 4 blocks. Let’s fill in the these numbers in the Students will find unknown addends to solve story number sentence format to show this. [Together with the class, problems. fill in 4 = 3 + 1. Discuss that in this equation the sum is placed Students will write equations with the sum on the left on the left side of the equal sign and it is the same as when side and addends on the right side. the equation is flipped, with the sum on the right side of the MATERIALS NEEDED: 3 opaque bags or containers; equal sign. red and yellow blocks; blank papersCommon Core Standard: CCSS2.OA.1 Repeat the process again, using 4 as the whole and filling in the math puzzle with another combination of numbers that LESSON WARM-UP adds up to 4. Discuss with students that this is another way to make 4, and elicit the third combination. Review facts for fluency using the My Math Facts practice booklet. II. Checking a non-example THINKING TRIGGER Ask: How about 3 and 2? Could Jake have 3 red blocks and 2 yellow blocks if he has 4 blocks in all? Can we fill in those as parts What are some of the math puzzles we can make using that make 4 as a whole? How can we check? [by adding 3 + 2] 5 as the whole? What is 3+2? [5] So 4 is not 3 + 2 [Write 4 = 3 + 2, and draw an X over it to show that it cannot be that Jake has 3 red blocks and 2 yellow blocks in his bag.] At this point, find Jake’s bag and reveal what the actual contents of the bag are.CONCEPT DEVELOPMENT STUDENT TEACHER Copyright © by SPOTS Educational Resources. All rights reserved.I. Using a story problem to introduce the Tell the class another story: Henri counted 8 coins in his bank. concept of “two unknown addends.” Some are pennies and some are nickels. Let’s use a math puzzle to help us find the number of pennies and the number of nick-In advance of the lesson, prepare three opaque bags or els Henri could have. [Place or draw 3 math puzzles on thecontainers, each containing red and yellow blocks, four board.] How many coins are there in all? [8] Our whole is 8. [Fillblocks in per bag. Make sure to put a different combination it in for each puzzle.] Now that we have the whole, we need toof two colors in each bag (1 red block and 3 yellow blocks; 2 find the two parts – the number of pennies and the number ofof each color; 3 red blocks and 1 yellow block). Label one of nickels. Copy the math puzzles onto your paper and find threethe bags Jake, but make sure that the label is not visible to ways to make 8 out of two types of coins. [Check each puzzlethe students. Tell the class: Jake has red and yellow blocks. He using a number sentence: 8 = ___ + ___. Have a few stu-put 4 blocks in his bag. What combination of blocks might he dents present their work. Ask:] Are there other ways, besideshave put in his bag? Let’s think about the number families for 4 these, to make 8? [Elicit other combinations.]and see what combinations of red and yellow blocks could be inJake’s bag.12

Using the Book: pages 13-14 Problem Solving: Both Addends Unknown Circle the number sentence that shows the correct addends. Write more than one possible pair of addends. Complete the math puzzle. Fill in the math puzzles for each story problem. 1. Brian has 10 marbles. 10 1. Melissa has 8 pieces of fruit. Some are red and some are blue. Some are grapes and some are cherries. Whole 8 8 Whole Whole 10 = 6 + 4 10 = 6 + 3 Part Part 2. Megan has 7 rocks. 7 Part Part Part Part Some are big and some are small. Whole 8= + 8= + 43 2. John has 5 apples. Some are red and some are green. Part Part 7=3+3 7=4+3 5 5 Whole Whole 3. Tami has 6 pens. 6 41 3 2 Some are blue and some are black. Whole Part Part Part Part 42 5= 4 + 1 5= 3 +2 6=4+2 6=5+2 Part Part 3. Hong took 7 photos yesterday. Some are of family and some are of friends. In what ways, could Hong have split the photos? 4. A store sold 9 stuffed animals. 9 7 7 7 Some are bears and some are lions. Whole Whole Whole Whole 9=7+2 9=7+3 72 6 1 43 52 Part Part Part Part Part Part Part Part 7=6 +1 7= 4 + 3 7= 5 + 2 14 Chapter 1 Lesson 6 OA.1 Problem Solving: Both Addends Unknown 13 Now let’s practice finding unknown addends when we know it together, and discuss the information that is given and the whole. When both addends are missing, we can fill in the information that is missing. Have students complete any two numbers that will add up to the whole amount. the tracing sample, leading them to see that the number Refer the class to the first story problem on page 13, read sentence is made up of two parts and a whole.Copyright © by SPOTS Educational Resources. All rights reserved. DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Some students may be troubled by the new presentation What did we learn today in math class? of an equation with the sum number on the left instead Today we learned how to solve story problems of on the right. You may wish to address this issue by with both addends missing. Tomorrow we will find drawing or modeling with blocks on a balance scale (e.g, 2 blue cubes, and 3 red cubes = 5 yellow cubes can be the unknown number in an equation. viewed either with the blue and red on the left and yel- low cubes on the right or vice versa). 13

Chapter 1 Lesson 7: Finding the Unknown Number INTRODUCTORY STATEMENT: counters] So if I have a whole and I subtract one part, I’m left Copyright © by SPOTS Educational Resources. All rights reserved. Yesterday we solved story problems by finding two with the other part. [Write the number sentence 9 – 2 = 7, unknown addends. Today we will use both addition labeling the numbers whole, part, part, respectively.] and subtraction to find unknown numbers. We will Summarize: Whole – Part = Part. use math puzzles to help us. Now let’s look at it the other way. [Cover the 7 black counters.] GOAL: If I take away the 7, what do I have left? [the other part – 2] Students will find the unknown number in math puz- Write the number sentence 9 – 7 = 2, labeling the numbers zles for addition and subtraction number sentences. whole, part, part, respectively. Summarize: The whole minus Students will use a to represent an unknown num- one part equals the other part. ber. MATERIALS NEEDED: cards with a math puzzle print- II. Using a box to represent an unknown ed on each one (see Student Teacher) numberCommon Core Standard: CCSS2.OA.2 On the board, draw or place a blank math puzzle with 6 and 4 filled in as the parts. Tell the class that we can always use LESSON WARMUP a box to represent a number in a number sentence that we don’t know (yet). Explain that since we don’t yet know what Review facts for fluency using the My Math Facts the whole is, we can draw a box in the top part of the puzzle. practice booklet. III. Solving to find an unknown number THINKING TRIGGER Say: Let’s write a number sentence to find the whole: 6 + 4 = . In the puzzle that is filled in with the numbers for 5, 3, What’s the sum of 6 + 4? It’s 10. We can fill in the box with 10, and 2, what are the parts and what is the whole? because 10 is the whole. How do you know? Summarize: When we know both parts, we add the partsCONCEPT DEVELOPMENT together to find the whole.I. Wholes and parts Draw or place another blank math puzzle on the board for the same number family of 6, 4, and 10, this time filling in theLay out 9 magnetic black-and-white counters on the board – 7 whole, 10, and one of the parts, 6. Say: In this puzzle we haveblack and 2 white. Place a math puzzle alongside them. Say: the whole and one of the parts. What are we missing? [the otherLet’s see what we have; one part of the group of counters is black part] What can we fill in instead of that number in the puzzle?– so 7 is one part. [Fill in 7 as a part.] Another part of the group [a box] [Draw an empty box in the puzzle for the other part.of counters is white – so 2 is another part. [Fill in 2 as a part.] Ask:] How can we find the missing part? [by subtracting 6 fromHow many counters in all? [9] So 9 is the whole. [Fill in 9 as the 10] [Write 10 – 6 = , and solve.] Now we can fill in the boxwhole in the puzzle.] with the number 4. When we know the whole and one part, weWrite the number sentence 7 + 2 = 9, labeling the numbers subtract to find the other part.part, part, and whole, respectively.Summarize: Part + Part = Whole IV. PracticeCover the 2 white counters with your hand. Say: If I havethe whole, and I take away one part, what do I have left? [the Draw or place a math puzzle on the board. Fill in 5 as theother part] How many do I still have showing? [7 – the 7 black whole, 4 as one part, and an empty box in the empty puzzle piece. Ask: When we know the whole amount and one part, how do we find the missing part? [by subtracting] [Draw an equation format, fill it in, and solve the equation together. Fill in the empty box in the puzzle with a 1.] 1 is the missing part. We found the unknown number! Draw or place another math puzzle on the board. Fill in the two parts with 5 and 1, and draw an empty box in the top puzzle piece. Ask: When we know both parts, how do we find the whole amount? [by adding] [Draw an equation format, fill14

Using the Book: pages 15-16 Finding the Unknown Number Write the number sentence to find the unknown number. We can use a to represent the unknown number. 1. 2. 3. When we know both parts, When we know the whole and 10 Whole 8 we add them together to find one part we subtract to find Whole 25 Whole the whole. the other part. 7 Part Part 4 Part Part Part Part Whole 8 10 – 7= 3 2 + 5= 7 8– 4= 4 35 Whole Whole Part Part Part Part Whole Whole Part Part Part Part 3 4. 5. 6. = Part Part Part Part Whole 9 6 Whole Whole Whole 46 Whole = 3 1 Part Part Part Part Part Part Part Part 4 + 6 = 10 Write the number sentence to find the unknown number. 9– 3= 6 6– 1= 5 Part Part Whole Whole Part Part Whole Part Part 9. 7. 8. 1. 2. 3. Whole 6 8 7 Whole 9 45 Whole Whole Whole 64 Whole Part Part 4 6 4 Part Part 2 5+ 4=9 Part Part Part Part Part Part 6 + 4 = 10 Part Part Part Part Whole 6 – 4=2 8 – 6 =2 7– 4 = 3 Part Part Whole 9– 2 = 7 16 Whole Part Part Whole Part Part Whole Part Part Whole Part Part Chapter 1 Lesson 7 OA.2 Finding the Number 15 Now let’s practice finding missing numbers by adding or Together with the class, read the text box at the top of page 15. subtracting, and filling in the box that shows where there’s an unknown number.Copyright © by SPOTS Educational Resources. All rights reserved. it in, and solve the problem together. Fill in the empty box DIFFERENTIATED INSTRUCTION in the puzzle with a 6.] Summarize: 6 is the missing whole. We found the unknown number! Some students may have trouble understanding that the largest number is always the whole. Use a basket contain- STUDENT TEACHER ing two kinds of blocks to demonstrate that the whole is made up of both parts, and that the amounts of the two Divide the class into pairs, and give each pair of students a types of blocks (the parts) can be added together to find deck of cards with a math puzzle printed on each card. First the total number in the basket (the whole). have the pairs fill in each math puzzle with two numbers (10 and under) and one box (for the unknown number). Then CLOSING STATEMENT: have them solve to find the value of the unknown number What did we learn today in math class? in each math puzzle. You may want to add a competitive Today we learned how to find the missing number element by having pairs race each other to beat the clock when we know the whole and one part, or when we and complete as many cards as possible. Review their work know the two parts but not the whole. Tomorrow we by calling on volunteers to show and discuss the process will find the unknown number in story problems. they used to find a solution. Ask: Did you add or subtract to find the missing number? [Elicit that if the whole is missing, 15 we add the parts; if one of the parts is missing, we subtract the other part from the whole.]

Chapter 1 Lesson 8: Finding the Unknown Number in Story Problems INTRODUCTORY STATEMENT: he read? [all the books; the whole] [Fill in the whole.] Three Copyright © by SPOTS Educational Resources. All rights reserved. Yesterday we found the unknown number in books are about planets. Is 3 the whole or a part? [a part – some math puzzles by adding or subtracting. Today we of the books he read] [Fill in 3.] Now we have the whole and will find the unknown number in story problems. one part. We need to find the other part – the number of books about animals. [Draw a box in the empty puzzle piece.] How GOAL: can we find the unknown part? [subtract] The whole minus one part equals the other part. [Draw an equation format, fill it in, Students will find the unknown number in story and solve it with help from the class.] What is the part? [5] Five problems. books are about animals.Common Core Standard: CCSS2.OA.1 II. Practice LESSON WARMUP Distribute sheets of paper with a blank puzzle printed on it.Tell another story, and have pairs of students repeat the processReview facts for fluency using the My Math Facts practice using a math puzzle to solve the problem. Say: Now you willbooklet. use a math puzzle to help solve the story problem: Jon counts 6 brown birds and 3 red birds at his bird feeder one morning. THINKING TRIGGER How many birds did Jon count? [Elicit from the students what the numbers in the story are telling us and what we need to Place a math puzzle on the board. Ask: How do you think find out (i.e., that both numbers are parts, and we need to math puzzles can help you solve story problems? find the whole – the number of birds in all).] How can we find the unknown number? [add] We will add the two parts to findCONCEPT DEVELOPMENT the unknown whole. [Have the partners fill in the math puzzle and write a number sentence, using a box for the unknownI. Using math puzzles to solve story problems number. Discuss the results.] There are 9 birds in all – that is the whole.Place or draw a math puzzle on the board. Say: I will tell a storyproblem that we can solve: Paulo has 7 animal stickers and 3 Summarize: When we know both parts, we add them togethercharacter stickers. How many stickers does Paulo have in all? to find the whole.We know that Paulo has 7 animal stickers. Is that the whole or apart? [a part; some of his stickers are animals, so that’s a part] Tell another story: Abe prepared 10 boxes of popcorn for a fair.[Fill in the puzzle as you go along.] 3 stickers are character Six were small boxes of popcorn and the rest were large boxes.stickers. Is that the whole or a part? [That’s also a part.] What How many large boxes of popcorn did Abe prepare?information is missing? [the whole; how many stickers in all]I will draw a box in that section of the puzzle to show that the Say: Again let’s show the story on a math puzzle. [Elicit fromwhole is missing. How can we find the whole? [add] We can add the students what the numbers in the story are telling usthe two parts to find the whole. [Write the equation 7 + 3 = , and what we need to find out (i.e., that the 10 boxes are theand solve.] Now we know that the whole is 10. [Write 10 in the whole – they are all the prepared boxes; the 6 small boxes arebox in the math puzzle.] Paulo has ten stickers in all. one part, and we need to find the other part – the numberPlace or draw another math puzzle on the board. Say: Now I of large boxes of popcorn).] How can we find the unknownwill tell another story problem for us to solve: Troy read 8 books number? [subtract] We will subtract the part we know from thethis month. Three of the books are about our planets. The rest whole to find the other part. [Have the partners fill in a mathof the books are about animals. How many animal books did puzzle and write a number sentence, using a box for theTroy read this month? We know that Troy read 8 books. Is 8 the unknown number. Discuss the results.] Abe prepared 4 largewhole or a part – is that all the books or some of the books that boxes of popcorn. Summarize: When we know the whole amount and one part, we subtract to find the other part.16

Using the Book: Complete pages 17-18. Finding the Unknown Number in Story Problems Ella has 9 T-shirts. We can use a to Fill in the math puzzle and write the number sentence. 5 T-shirts are colored. The rest are white. represent the unknown Use a for the unknown number. Solve. How many T-shirts are white? number. 1. There are 9 birds in a tree. 9 Whole –= Part 4 of the birds are blue. Part Whole How many of the birds are a Whole different color? –= Part Part 45 Number sentence: 9 – 4 = 5 5 of the birds are a different color. Part Part Whole Part Part T-shirts are white.. 2. Kevin has 5 books in a box. 3 books are hardcover. Write the number sentence and fill in the math puzzle. The rest are paperback. 5 How many paperback books are in the box? Use a for the unknown number. Solve. Whole Number sentence: 5 – 3 = 2 1. Natalie has 10 postcards. Kevin has 2 paperback books in the box. 32 7 postcards are from her grandparents. The rest are from her aunt. Part Part How many postcards are from Natalie’s aunt? 10 3. Carmella has 3 shiny stickers 9 and 6 fuzzy stickers. Number sentence: 10 - 7 = 3 Whole How many stickers does she have in all? Whole 7 Part Part Natalie has ___3___ postcards from her aunt. Number sentence: 3 + 6 = 9 3 6Part Part She has 9 stickers in all. 2. Jeremy has 8 pink balloons Whole 8 and 2 blue balloons. 4. Rosa listened to 8 songs. She liked How many balloons does Jeremy 82 5 of the songs. The rest she did not like. Whole have in all? How many of the songs did Rosa Part Part not like? 53 Number sentence: 8 + 2 = 10 Jeremy has __1__0___ balloons in all. Number sentence: 8 – 5 = 3 Part Part Rosa did not like 3 of the songs. Chapter 1 Lesson 8 OA.1 Finding the Unknown Number in Story Problems 17 18 Now let’s practice finding the unknown number in story using the math puzzles. Remind the class that for some problems. stories we need to add and for others we need to subtract. Read each story problem together with the class. Then have the students solve the problems independently,Copyright © by SPOTS Educational Resources. All rights reserved. STUDENT TEACHER DIFFERENTIATED INSTRUCTION Draw a math puzzle on the board, and fill in the whole with Some students may have trouble discerning that “all of 9. Have a volunteer suggest another number less than 9 to something” makes a whole even when the objects are fill in as one of the parts. Write an equation format beneath disparate. To address this confusion, discuss examples the puzzle. Have a volunteer tell a math story for the puzzle. from students’ daily life, such as snacks: 2 bags of chips Ask: When we know the whole and one of the parts, how can and 3 bags of pretzels together make all the snack bags, we find the unknown number? [Elicit that we subtract the so the whole is 5, and 2 and 3 are the parts. part we know from the whole. Together, fill in the missing numbers in the puzzle and complete the equation.] CLOSING STATEMENT: What did we learn today in math class? Today we used math puzzles to help us find the unknown number in story problems. Tomorrow we will add numbers in which one addend and the sum are teen numbers. 17

Chapter 1 Lesson 9: Adding to Teen Numbers INTRODUCTORY STATEMENT: Write 15 + 4. Say: I’m going to use what I know to help me So far we’ve added numbers with sums up to ten. find the sum. [Write 5 + 4.] I know that 5 + 4 equals 9. [Fill Today we will use what we know about that to in the sum.] I know that 15 + 4 is similar, but it has a ten. If 5 + 4 = 9, then 15 + 4 = 19. [Use Dot Cards to show the add to teen numbers. equations.] We used 5 + 4 as a helping number sentence to help us solve 15 + 4. GOAL: III. Using a number sentence to help Students will solve addition equations in which one addend and the sum are teen numbers. Say: Now let’s try this without the Dot Cards. [Write 13 + 5 MATERIALS NEEDED: addition equation cards with and draw a number-sentence format underneath it (see p. equations learned in this lesson; blank sheets of paper 13 of the Student’s Edition).] Which number sentence that we know can help us solve this? [3 + 5 or 5 + 3] [Fill in the number-Common Core Standard: CCSS2.OA.2 sentence format.] What is the sum of 3 + 5? [8] [Fill in the sum.] If we know that 3 + 5 = 8, then we know that 13 + 5 = 18. [Fill in LESSON WARMUP the sum: 18.] [Repeat with 14 + 5 and 12 + 3. Solve using the thinking process described above.] Review facts for fluency using the My Math Facts practice booklet. Write 10 + 5 on the board. Ask: Do we need a helping number sentence to help us solve this? [no; we just need to add the ones] [Ask a student to solve this and fill in the sum.] THINKING TRIGGER IV. Adding by counting on Copyright © by SPOTS Educational Resources. All rights reserved. What are teen numbers? Write 16 + 2 on the board. Ask: How much are we adding here? [2] We are adding just 2. We can count on two to find the sum.CONCEPT DEVELOPMENT We begin with 16 and count on: 17, 18. [Fill in the sum.] When adding a small number to a teen number, we can also count onI. Teen numbers to find the sum. [Repeat with 18 + 1.]List the numbers 11-19 on the board. Read the list together Write 13 + 3. Ask: How would you solve this? Would you think ofand ask: What is special about these numbers? [Encourage a helping number sentence, or would you count on? [Point outstudents to suggest as many common characteristics as that either way is correct, and solve the equation both ways.]possible. List them on the board. Include: teen numbers; twodigits; each has a ten and ones.] V. Adding mentallyDisplay the Teen Dot Cards and discuss what they show: Eachhas a ten and ones. Now we will have a challenge. [Write 14 + 4 = ___ on theTogether with the class, tell the number each Dot Card shows. board.] Can you tell us the sum without having us write a helping number sentence? Just think of it in your head. What is the sum?II. Adding to teen numbers using Dot Cards [18] What number sentence did you think of? [4 + 4 = 8] and counters Do the same for 11 + 3 and 13 + 4.Write the equation pair: 14 + 3 and 4 + 3. Discuss how theyare similar (both equations have the same number of ones) STUDENT TEACHERand how they are different (14 + 3 has a ten).Show the equations with Dot Cards, and solve. Say: The sums Divide the class into pairs. Give each pair a sheet of paperare also similar. Each sum has seven ones, but the sum of the and two teen addition equation cards. Have the partnersfirst number sentence also has a ten, so it equals 17. write the teen equations and solve them, either by using number sentences to help or by counting on. Have the partners share and compare their thinking processes. Elicit that when we are adding a small amount it may be easier to count on, but when we are adding a larger amount, a help- ing number sentence is usually quicker to use.18

Using the Book: pages 19-20 Adding to Teen Numbers Add. 1. 2. 3. 4. Add. 14 + 3 = _1_7_ 10 + 6 = _1_6_ 15 + 4 =_1_9_ 17 + 2 =_1_9_ 1. 2. 3. 4. 5. 6. 5. 6. 7. 8. 1 11 4 14 2 12 +5 +5 +3 +3 +7 +7 13 + 5 = _1_8_ 12 + 4 = _1_6_ 11 + 8 = 1__9_ 12 + 6 = 1__8_ 16 17 19 6 7 9 9. 10. 11. 12. 8. 7. 9. 10. 11. 12. 10 + 9 = _1_9_ 13 + 4 = _1_7_ 14 + 5 = 1__9_ 16 + 3 = 1__9_ 13 3 +5 1 11 3 13 13. 14. 15. 16. +5 18 +6 +6 +3 +3 17 16 12 + 2 = _1_4_ 11 + 4 = _1_5_ 13 + 6 = 1__9_ 14 + 4 = 1__8_ 8 7 6 Write the number sentence that will help solve the exercise. Solve. 13. 14. Fill in the math puzzle and write the number sentence. Use a for the unknown number. Solve. 12 + 6 = 18 15 + 4 = 19 2+6=8 5+4=9 17. Rafael has 10 carrot sticks. 15 He has 5 celery sticks. 15. 16. How many vegetable sticks does Rafael have? Whole 11 + 7 = 18 13 + 6 = 19 Number sentence: 10 + 5 = 15 10 5 Part Part Rafael has 15 vegetable sticks. 1+7=8 3+6=9 18. Kelli has 10 bananas. 14 She buys 4 oranges. 17. 18. How many pieces of fruit does Kelli have? Whole 12 + 5 = 17 14 + 4 = 18 Number sentence: 10 + 4 = 14 10 4 Kelli has __1__4___ pieces of fruit. 2+5 = 7 4 + 14 = 8 Part Part 20 Chapter 1 Lesson 9 OA.2 Adding to Teen Numbers 19 Now let’s practice adding to teen numbers. point out that the whole is the category and the parts are For the story problems in examples 17 and 18 on page 20, specific items. DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Some students may have trouble keeping track of place What did we learn today in math class? value and adding to the ones instead of to the tens. Today we added to teen numbers. Tomorrow we will Along with the strategies in this lesson, have them cover the 1 in the tens column with their finger or with a sticky add numbers with sums that are more than ten. note until after they have added the two sets of ones.Copyright © by SPOTS Educational Resources. All rights reserved. 19

Chapter 1 Lesson 10: Adding in Two Steps INTRODUCTORY STATEMENT: on the tens side and six white counters on the ones side). Copyright © by SPOTS Educational Resources. All rights reserved. Yesterday we learned about number sentences with Ask: What number sentence does this show? [9 + 6] [Write the equation on the board.] We have nine black counters and six teen numbers. Today we will learn about adding white counters. Try to make a ten on your Dot Board to solve this numbers whose sums are teen numbers. equation. [Allow students time to do so. Ask some of them to We will add in two steps. tell what they did. Move a white counter over to the tens side of the Dot Board, and have the class do the same.] How many GOAL: counters are there on each side? [10 on the tens side and 5 on the ones side] How many are there altogether? [15] Now that Students will solve equations with sums that are teen we’ve filled the tens side of the board, it’s easy to see how many numbers, using two steps. there are in all. How much is 9 + 6? [15] [Fill in the sum. Repeat MATERIALS NEEDED: blank papers; colored stickers; this activity with 8 + 8, and stress that when you make a ten Teen Dot Boards and counters first, you can easily see how many there are in all.]Common Core Standard: CCSS2.OA.2 III. Adding without moving counters LESSON WARM-UP Write the equation 8 + 6 = ___ on the board. Place six white counters on the right side of the 8+ Dot Board. Have Review facts for fluency using the My Math Facts practice the students set up their Dot Boards in the same way. Ask: booklet. What number sentence does this show? [8 + 6] How many more counters does 8 need to make ten? [2] Let’s do something THINKING TRIGGER different. Let’s think of how we can show this without moving any counters to another place. How can we leave the counters Write the equation 9 + 7 = ___ on the board. Ask: How can in their places and still make a ten? [Accept suggestions. Then, we show this on a Teen Dot Board? on the board, turn over the upper two white counters and say:] We can turn these counters over to their black side to showCONCEPT DEVELOPMENT that we need them to make the ten, and we can draw an arrow to show that they are “flying over” to make the ten. [Draw anI. Exploring making a ten arrow from the turned-over black counters on the ones side to the empty spaces on the tens side of the Dot Board.] NowHand out a blank paper and the following set of stickers to I don’t need to move the counters over. I can leave them in theireach student: seven blue, four red, and three green. Say: Let’s places, turn them over to the black side, and imagine that theystick these onto our papers in a way that will make it easy to see are “flying over” to make a ten. [Have the students similarlyhow many we have in all. What do you think is the best way to do turn the upper two white counters to the black side andthat? [Accept suggestions.] Let’s first put together some of the draw an arrow to show them “flying over” to make the ten.]stickers to make a ten. Which groups of stickers together make Can you see how many counters stayed white? [4] How manyten? [blue and green] [On the board, demonstrate placing do we have altogether? [14] [Write the sum.]those stickers in a Dot Card format.] Now let’s put the otherstickers next to them. Can you see how many we have in all? [14] Repeat this process with 7 + 5.Hand out a set of eight yellow and three orange stickers. Say:Use the other side of the paper to stick these down in a way that IV. Writing “break-apart numbers”makes it easy to see how many there are. Remember, it’s a goodidea to first make a ten. [Have some students share their work Write 8 + 5 on the board, and show it on a Dot Board withwith the class.] counters. Say: I see that this sum is greater than ten. First we need to make a ten. How many more do we need to make aII. Using Dot Boards to make a ten ten? [2] We will break apart the 5 to get those two more. [Turn two counters over to the black side.] Three counters stayedDistribute a Teen Dot Board and 16 counters to each student. white. We broke apart the 5 into 2 and 3. [Under the 5, drawPlace the 9+ Dot Board on the board, and put six white two spaces for the break-apart numbers (see page 21 in thecounters on the right side of the Dot Board. Instruct the class Student’s Edition), and write in 2 and 3.] 2 and 3 are our break-to do the same on their Dot Boards (nine black counters apart numbers. What is the sum of 8 and 5? [13] We have 13 in all. [Fill in the sum.]20

Using the Book: pages 21-22 Adding in Two Steps When the sum will be more than 10, Color the dots and draw an arrow to make a ten. we add in two steps: Fill in the break-apart numbers and write the sum. First we add to make a ten. 1. 2. 3. Then we add the rest to the ten to get the sum. 28 + 6 = 144 We break apart the 6. to make ten the rest 2 and 4 are the break-apart numbers. Color the dots and draw an arrow to make a ten. 9 + 8 = 17 7 + 5 = 12 7 + 7 = 14 Fill in the break-apart numbers and write the sum. 17 32 34 1. 2. to make ten the rest to make ten the rest to make ten the rest 3. 4. 5. 6. 9 + 9 = 18 8 + 7 = 15 9 + 6 = 15 6 + 5 = 11 8 + 8 = 16 7 + 4 = 11 41 26 31 1 8 2 5 1 5 to make ten the rest to make ten the rest to make ten the rest 4. 5. 6. to make ten the rest to make ten the rest to make ten the rest Fill in the math puzzle and write the number sentence. Use a for the unknown number. Solve. 7. Bob has 8 picture books. 14 He also has 8 storybooks. How many book does Bob have in all? Whole 7 + 6 = 13 8 + 5 =13 6 + 6 = 12 Number sentence: _8__+__6___=__1_4____ 86 Bob has _1_4_ books in all. 3 3 2 3 4 2 Part Part to make ten the rest to make ten the rest to make ten the rest Chapter 1 Lesson 10 OA.2 Adding in Two Steps 21 22 Now let’s practice the make-a-ten strategy by adding to ten, and then adding past ten.Copyright © by SPOTS Educational Resources. All rights reserved. STUDENT TEACHER DIFFERENTIATED INSTRUCTION On the board, write 8 + 7, and place the 8+ Dot Board Some students may be unsure of which set of break-apart with seven white counters next to it. Repeat with 9 + 8 numbers to use to fill in the blanks. Remind them that and 6 + 5, placing the 9+ and 6+ Dot Boards and a number of the first break-apart number will always be equal to the additional counters on the board. Call up three volunteers to number of empty boxes on the tens side of the teen Dot solve the problems. Instruct the students to use the make- Board. a-ten strategy and write the break-apart numbers they used to solve each problem. Then discuss their strategies. CLOSING STATEMENT: Elicit or emphasize that when addling with a sum that is What did we learn today in math class? more than ten, it is helpful to first add mentally to make a Today we learned to add two numbers ten, and then add the rest. One method for doing this is to flip over the counters that make a ten to the black side and whose sum is a teen number. then add the rest. Tomorrow we will practice this more. 21

Chapter 1 Lesson 11: Practice: Addition with Teen Sums INTRODUCTORY STATEMENT: For which of these number sentences would we use break-apart Copyright © by SPOTS Educational Resources. All rights reserved. Yesterday we added numbers using two steps. numbers? [7 + 5] When the sum will be more than 10, it is easier We found sums by first making a ten and then to break apart the second addend to first make ten and then adding the rest. Today we will practice this more. add the rest to the ten. [Solve 7 + 5 using a Dot Board and counters, and write the break-apart numbers.] GOAL: In the same way, write 8 + 2 and 8 + 5 on the board, decide Students will practice addition with sums that are teen which has a sum that is more than ten, and solve that numbers. equation as above. MATERIALS NEEDED: small squares of paper (three per student) Give each student three small squares of paper. Write the number 7 on the board. Ask the students to write a (single-Common Core Standard: CCSS2.OA.2 digit) number on one of their papers that, when added to the number on the board, will equal more than ten. Ask the LESSON WARM-UP students to show their numbers by raising them above their heads. Choose a few numbers to add, write the equations on Review facts for fluency using the My Math Facts practice the board, and solve them together. booklet. Write the number 6 on the board. Ask the students to write THINKING TRIGGER a number on their second paper that, when added to the number on the board, will equal less than ten. Continue as Yesterday we talked about adding in two steps, using above. break-apart numbers. When do we add in this way? Repeat this activity as needed.CONCEPT DEVELOPMENT III. PracticeI. Adding in two steps Place the First-Addend Dot Boards on the board. Write 7 +On the board, write 8 + 7 = ___, and place the 8+ Dot Board 6 = ___. Ask: Which Dot Board should we use to help us solveand seven white counters next to it. Under the 7 draw two this problem? [the 7+ Dot Board] This time we won’t use whitespaces for the break-apart numbers. Ask: How many more do counters for the second addend. Instead, we will pretend. Howwe need to add to the 8 to make a ten? [2] Let’s pretend the two many white counters would we need? [6] How many do we needwhite counters are flying over to make a ten. How many counters to make 10? [3] Let’s imagine turning over three white counters,stay white after we make a ten? [5] What are the break-apart and then we add the rest. So 7 + 3 = 10, and then 10 + 3 = 13. 13numbers? [2, 5] [Write 2 and 5 in the spaces under the 7.] is the sum. [Repeat with 8 + 5, 9 + 7, and 6 + 5.]What is the sum? How much is 8 + 7? [15] [Fill in the sum andrepeat, pointing to the numbers on the board as you speak:] Write 4 + 8. Ask: Which Dot Board should we use to help us solveWe had 8 + 7. We needed to make a ten. We broke apart the 7 this problem? [the 8+ Dot Board] Why? [because it’s easier tointo 2 and 5. 8 plus 2 equals 10, and 5 more equals 15. think of the greater addend first] [Continue as above. RepeatRepeat the process with 9 + 5 and 7 + 4. with 2 + 9.]II. Deciding whether the sum is more than ten STUDENT TEACHERWrite 7 + 2 = ___ and 7 + 5 = ___ on the board. Ask: Is 7 + 2 On the board, write addition equations in which the sec-equal to more than 10? [No; it equals only 9.] Is 7 + 5 equal to ond addend is greater than the first addend. Have studentsmore than 10? [yes] How do you know that? [7 + 3 = 10; 7 + 5 come up to the board in turn to solve the equations. Haveis more than that.] each student explain how he/she will solve the problem. Discuss with the class whether it is an efficient method. Elicit that it is more efficient to make a ten first, and that this is most easily accomplished by adding to the larger addend. So reversing the order of the addends will make the addi- tion process quicker.22

Using the Book: pages 23-24 Practice: Addition with Teen Sums Circle each number sentence whose sum is more than ten. Add. Color the dots and draw an arrow to make a ten. Fill in the break-apart numbers and write the sum. 1. 2. 3. 1. 6 2. 6 3. 8 4. 8 5. 9 6. 7 +3 +5 +1 +4 +9 +2 9 11 9 12 18 9 9 + 9 = 18 8 + 7 = 15 9 + 6 = 15 7. 8 8. 6 97 10. 4 11. 9 12. 6 +9 +4 +5 +4 +7 +9 1 8 2 5 1 5 17 10 12 8 16 15 to make ten the rest to make ten the rest to make ten the rest Add. Remember: We can think of the greater number first. 4. 6 + 9 = 15 7. 3 + 8 = 11 10. 7 + 9 = 16 13. 7 14. 9 15. 8 16. 6 17. 4 18. 8 +3 +5 +6 +2 +7 +7 5. 5 + 9 = 14 8. 6 + 8 = 14 11. 8 + 9 = 17 10 14 14 8 11 15 6. 3 + 9 = 12 9. 7 + 8 = 15 12. 4 + 9 = 13 LET’S WRITE! 13. 5 + 7 = 12 16. 5 + 6 = 11 19. 5 + 8 = 13 Look at exercise number 18. Explain how you solved 8 + 7. 14. 6 + 7 = 13 17. 6 + 6 = 12 20. 4 + 8 = 12 15. 4 + 7 = 11 18. 4 + 6 = 10 21. 8 + 8 = 16 Answers will vary. Sample answer: I split 7 into 2 + 5 to make a ten to get 10 + 5 = 15. Chapter 1 Lesson 11 OA.2 Practice: Addition with Teen Sums 23 24 Now let’s practice adding numbers, using the make-a-ten strategy.Copyright © by SPOTS Educational Resources. All rights reserved. DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Refer students to the Dot Cards pictured at the bottom What did we learn today in math class? of each of the student pages to help them add. Remind Today we practiced adding numbers with sums them to select the Dot Card that represents the larger ad- that are teen numbers. Tomorrow we will add dend, and to add on to it by first completing the ten and then adding the rest. on number lines. 23

Chapter 1 Lesson 12: Using the Number Line to Add INTRODUCTORY STATEMENT: amount. [Have Bunny make one long jump that would cover Copyright © by SPOTS Educational Resources. All rights reserved.Yesterday we practiced adding numbers in two steps. five spaces. Draw the jump and write in +5.] Bunny jumped five. On which number did he land? What is 5 plus 5 more? [10] Today we will use a number line to show [Write in 10.] Now our number line shows 5 + 5 = 10. [Read the adding numbers whose sums are teen numbers. equation on the board and fill in the sum.] GOAL: Do the same with 7 + 3. Students will use an open number line to show addition II. Adding to ten with one jump with two numbers, by making two jumps: one jump to the ten and another jump to the sum. On the board, write 10 + 6 = ___, and draw an open number MATERIALS NEEDED: “Bunny” – a small toy rabbit or line next to it. Say: Let’s help Bunny add. What number should a rabbit cutout; blank sheets of paper we fill in at the beginning of the number line? [10] [Write 10.] How many does Bunny need to jump? [6] [Have Bunny make aCommon Core Standard: CCSS2.OA.2 jump of 6. Draw the jump, and write in +6.] On what number did Bunny land? [16] Our sum is 16. [Write 16 at the end of the LESSON WARMUP jump, and fill in the sum in the equation.] Review facts for fluency using the My Math Facts In the same way, use Bunny to show 10 + 8. practice booklet. III. Making two jumps THINKING TRIGGER On the board, write 8 + 5 = ___, and place the 8+ Dot Board Write 9 + 6 = 15 on the board. Draw an open number line. with 5 white counters next to it. Review the process of making Ask: How do you think can we show this number sentence a ten and then adding the rest to the ten. Draw spaces for the on a number line? break-apart numbers, and ask the class help you fill them in. Say: Now Bunny will show this on a number line.CONCEPT DEVELOPMENT Draw an open number line, and begin the number line withI. Adding numbers that equal ten with one 8. Say: Here we will start with 8, because it is the first addend. jump [Refer to the Dot Card and the break-apart numbers as you continue.] How did we solve this number sentence? [in twoDisplay the toy rabbit or the rabbit cutout. Ask: Remember steps; first we added to ten, and then we added the rest toBunny? How does he jump? [He jumps a few numbers at a the ten] So Bunny will make two jumps to show the two steps.time.] First he will jump to 10, then he will jump the rest, to the sum.Write 5 + 5 = ___ on the board, and draw an open number How many white counters did we need to make a ten? [2] Bunnyline. (An open number line is a line without a beginning or will make a jump of 2 to get to ten. [Show a +2 jump on thean end, and without numbers written on it. It can be used number line.] On which number did he land? [10] [Write into make jumps of various lengths. For examples, see pages the number ten.] Now Bunny will make a jump of 3 to get to27-28 in the Student’s Edition.) Begin the number line with the sum. [Draw the second jump and label it +3.] On which5, and place Bunny at that point. Say: Now Bunny wants to number did we land? [13] [Write the sum (13) at the end ofsolve this on the number line. How many does Bunny need to the second jump.] First we made a jump of 2 to get to ten, andjump? [5 more] Remember that Bunny can jump the whole then we made a jump of 3 to get to the sum, 13. When we firstnumber at once? Let’s help him make one big jump for the whole add to ten, and then add the rest of the number, it’s easy to find the sum. How many jumps did we make? [2] Bunny jumped 5 in two jumps: a jump of 2 and a jump of 3 – the same as the break- apart numbers. Repeat the process with 7 + 5 and 9 + 7. For each, first solve using the Dot Board and counters, and write the break-apart numbers. Then have Bunny show it on the number line, and summarize as above.24

Using the Book: pages 25-26 Using the Number Line to Add We make two jumps on the number line: Complete the number line. First we jump to the ten. Fill in the sum. 1. +6 + + + 6 + 5 = 11 +4 +1 8+6= 8 2. 10 11 Complete the number line. Fill in the sum. 7 + 5 = 12 + +3 +2 1. +7 +6 3. +1 10 12 9 + 7 = 16 9 10 8 + 8 = 16 16 ON YOUR OWN! + +2 2. +5 4. +6 16 +2 +3 10 8 + 5 = 13 8 10 13 3. +6 15 8 + 7 = 15 +1 + 5 9 + 6 = 15 9 10 4. +7 14 Add. 6. 8 7. 6 8. 2 9. 7 10. 4 +3 +4 +5 +6 +9 +7 +8 7 + 7 = 14 7 10 5. 9 13 12 11 14 12 +8 Chapter 1 Lesson 12 OA.2 Using the Number Line to Add 25 17 26 Now let’s practice using the number line to add in two steps. ond addend above the number line, draw the jumps, and fill For page 28, exercise 4, direct students to fill in the sec- in the two break-apart numbers along the number line.Copyright © by SPOTS Educational Resources. All rights reserved. STUDENT TEACHER DIFFERENTIATED INSTRUCTION Write the following equations on the board: 7 + 6, 9 + 8, 8 Some students may have trouble solving the vertical ad- + 6, 7 + 7, 6 + 5, and 9 + 6. Divide the class into pairs. Give dition problems. Remind them that they can think of Dot each student a blank sheet of paper. Have each pair choose Cards, break-apart numbers, or number lines. They can one equation to solve. Have one partner solve the equation also use the Dot Card banner to help them. using break-apart numbers, and have the other partner solve it on an open number line. Then have the partners CLOSING STATEMENT: compare their work; the break-apart numbers and the num- What did we learn today in math class? Today we bers of the jumps, and the sums, should all be the same. practiced showing addition by making two jumps on Have the partners switch roles to solve another problem. a number line. Tomorrow we will review the different Ask: How did the number line help you solve your equation? ways we add, and each of you will decide on the way [Elicit that the number line can help you think of the two steps as two jumps: one jump to 10 and one jump past 10.] that is best for you. 25

Chapter 1 Lesson 13: Choosing a Way to Add INTRODUCTORY STATEMENT: see if you can tell me the answer! The question is: How much is 7 Copyright © by SPOTS Educational Resources. All rights reserved. We’ve learned different ways to add to teen + 6? [Write 7 + 6 on the board.] David, Michael, and Danny all numbers. Today we will think about those ways and thought for a moment, and then all three said at once: I know! decide which way works best for each of us. It’s 13! GOAL: Miriam asked them: How did you figure it out so quickly? Students will choose the method that they prefer when David said: I thought about a picture of the Dot Card with adding with sums that are teen numbers. counters, and I thought about what it would look like to color MATERIALS NEEDED: three sheets of paper for each in three dots to make a ten. 10 dots and 3 dots more make 13! student; large timer, numbered cards, or numbered flip- [Place a 7 + 6 Dot Card on the board.] chart Michael said: I didn’t do it that way. I thought of breaking apartCommon Core Standard: CCSS2.OA.2 numbers to make a ten. I thought that I need three to make a ten, and then another 3, which makes 13. [Write the number LESSON WARMUP sentence and the break-apart numbers on the board.] Review facts for fluency using the My Math Facts Danny laughed and said: And I did something else! I thought of practice booklet. a number line. I started with seven, jumped three to the ten, and three more to 13! [Draw and fill in a number line accordingly. THINKING TRIGGER Point out that each friend used a different way to solve Miriam’s equation, and that each one is correct. Everyone Write 8 + 6 = ___ on the board. Ask: What are some ways finds a way that works best for him or her.] we can solve this? [Show the different ways, but it is not necessary to solve the equation.] Hand out three sheets of paper to each student. Have the students draw an open number line on the first sheet ofCONCEPT DEVELOPMENT paper. Write 8 + 5 on the board. Have the students solve theI. Reviewing addition using Dot Cards problem using the number line, and when they are done have each of them mark how long it took. (You can displayWrite 7 + 7 on the board. Have the class tell you how to show a large digital stopwatch, or you can flip numbered cardsit using a Dot Board and counters. at an even pace, so that they can time themselves.) Tell the students to mark on their papers how long it took them toII. Reviewing addition using a number line solve the equation using the number line.Write 9 + 8 on the board. Have the class tell you how to show Write 9 + 7 on the board. Have the students solve the problemit on a number line. using break-apart numbers on the second sheet of paper, while you time them. Have them write on their papers howIII. Reviewing addition with break-apart long it took them to solve it. numbers Have the students draw a blank double Dot Card on the thirdWrite 8 + 4 and solve together with the class: Discuss how paper. Write 7 + 5 on the board, and have them fill in the Dotto break apart the 4 (2, 2), draw spaces for the break-apart Card to solve it while you time them. Ask them to think aboutnumbers, and fill them in. Then write the sum. which way was easiest for them and which way was quickest. Point out that easiest and quickest are not always the same,IV. Choosing a method to add and that all the methods are good ones.David, Michael, and Danny are friends. David’s sister Miriam said V. Reviewing addition using a number lineto the friends: I have a challenge – a hard question for you. Let’s Say: I will tell a story. I want you to solve the problem on your paper by adding using the way that works best for you. David has 8 blue marbles and 7 green marbles. How many does he have altogether?26

Using the Book: pages 27-28 Add. Choosing a Way to Add Add. Choose the way that works best for you. Solve. 7+6= Which way works best for you? 1. 9 + 7 = 16 2. 6 + 6 = 12 I like to use the I like to use the Dot Card. break-apart number sentence. 7 + 6 = 13 33 to make ten the rest 9 + 7 = 16 6 + 6 = 12 16 4 2 to make ten the rest to make ten the rest I like to use +7 +6 the number line. 1 2 +6 9 10 6 4 10 12 +3 +3 13 16 6 10 7 Circle the way that works best for you. Solve. Add. 1. 8 + 6 = 14 2. 7 + 5 = 12 3. 9 4. 4 5. 7 6. 6 7. 7 8. 3 +8 +7 +6 +5 +7 +8 17 11 13 11 14 11 8 + 6 = 14 7 + 5 = 12 Write the number sentence and solve. 2 4 3 2 to make ten the rest to make ten the rest 9. Pat had 8¢. Her dad gave her another 5¢. +6 +5 How much money does she have now? 13 ¢ +2 +4 14 +3 +2 Number sentence: 8¢ + 5¢ = 13¢ 8 10 7 10 12 Chapter 1 Lesson 13 OA.2 Choosing a Way to Add 27 28 Now we will practice using a variety of methods to add to a Review the students’ answers, and have them share the teen sum. methods they used to complete each example.Copyright © by SPOTS Educational Resources. All rights reserved. Give the students time to write the number sentence and DIFFERENTIATED INSTRUCTION solve the problem using one of the methods they learned. Then ask a few students to describe how they chose to solve Some students may have had trouble integrating all three it and why. Repeat this activity with another story. methods discussed in this chapter. Use this lesson as an opportunity for students to examine all the methods side STUDENT TEACHER by side and see what makes them similar to and different from each other. This should help deepen their under- Write 9 + 6 = on the board. Call up three students to solve it, standing of how the “completing a ten” strategy can make each using a different method. Ask: What do all these meth- the process of finding a teen sum more intuitive. ods have in common? [Accept a variety of answers. Elicit that each method utilizes the strategy of completing a ten and CLOSING STATEMENT: then adding the rest, but in different ways: tangibly, visually, and mentally.] What did we learn today in math class? Today we solved addition examples using different ways: Dot Cards, number lines, and break-apart numbers. We thought about which way works best for us. Tomorrow we will learn something new: adding three addends together. 27

Chapter 1 Lesson 14: Adding Three Addends INTRODUCTORY STATEMENT: make ten. When we add a few numbers together, we can first Copyright © by SPOTS Educational Resources. All rights reserved. We’ve already learned that we can add numbers in check to see if we can make a ten. Once we have a ten, it’s easy any order. Today we will learn to add three numbers to add the third addend. [For each equation, ask the students together. We will see that we can do this in the order which numbers make ten, circle them, add them, and then add the third addend.] that seems easiest to us. On the side of the board write a list, beginning with: GOAL: When you add a few numbers… Look for numbers that Students will find the sum of three addends. make a ten. MATERIALS NEEDED: blank sheets of paper; dice III. DoublesCommon Core Standard: CCSS2.OA.2 Write 6 + 2 + 6 = ___ on the board. Ask: Are there numbers LESSON WARMUP here that make a ten? [no] What else can we do? [Accept suggestions.] I see a doubles fact. 6 + 6 is easy – it equals 12. I Review facts for fluency using the My Math Facts would first add these together. [Circle the sixes.] 6 + 6 = 12, plus practice booklet. 2 more equals 14. When we see a doubles fact, we can add the doubles first. THINKING TRIGGER On the board, write: 2 + 7 + 7 = ___, 8 + 3 + 8 = ___, and 6 + Did you ever need to add more than two numbers 3 + 3 = ___. For each equation, ask the students to tell you together? How did you do that? which numbers are doubles. Circle them and add them first, and then add the third addend. Write in the sums. Add to theCONCEPT DEVELOPMENT list on the board: Look for doubles facts.I. Introducing the concept through a story IV. Adding the two larger numbers firstSome friends went to a store to buy prizes. They needed to buy Write 5 + 7 + 6 = ___. Say: There aren’t any numbers here that18 prizes in all. They chose 8 pencils, 3 key chains, and 7 Super equal ten, and I don’t see any doubles. I will look for the twoBalls. [Draw or list the prizes on the board and write the largest numbers. [Circle 7 and 6.] 7 and 6 equal 13. 5 moreamount they bought under each prize.] Now the friends need equals 18.to see if they have enough prizes. Can you help them figure outhow many prizes they bought in all? There were 8 pencils, 3 key On the list write: Add the two largest numbers first.chains, and 7 Super Balls.Write a number sentence (8 + 3 + 7 = ___), and accept Write: 2 + 4 + 7 = ___, 3 + 4 + 5 = ___, and 4 + 5 + 8 = ___. Havesuggestions for how to add the numbers together. Encourage students tell you which numbers are the largest numbers,using a variety of ways. Point out that the sum will be the circle those, and solve the equation together.same no matter in what order the numbers are added.8 + 3 + 7 = 18. 18 prizes in all. The friends have enough prizes! V. Practice Review the list of methods on the board. Explain that adding in any order that they would like is also correct. Add to the list: Add in any order. On the board, list: 3 + 8 + 3 = ___, 6 + 8 + 1 = ___, and 9 + 3 + 1 = ___. For each equation, decide which numbers to add first, circle them, and solve the equation.II. Making a tenOn the board, write 5 + 5 + 8 = ___, 9 + 4 + 1 = ___, and 3 + 6+ 7 = ___. Say: Each of these equations has two numbers that28

Using the Book: pages 29-30 Adding with Three Addends These are Team A’s points. I first added to Circle the addends you will add first. Add to find the total. make a ten. Write the new number sentence and solve. 473 1. 6 + 5 + 4 = 15 2. 8 + 6 + 3 = 17 I added the numbers 4+ 7 + 43S=u=z1y414points 10 + 5 = 15 14 + 3 = 17 in order. + 10 3. 7 + 9 + 2 = 18 4. 7 + 5 + 1 = 13 4 + 7 + 3B=ella14 points 11 + 3 = 14 I first added 9 + 9 = 18 8 + 5 = 13 to make a doubles fact. 5. 8 + 5 + 6 = 19 6. 3 + 6 + 6 = 15 4+ 7+ 3K=el1ly4 points 13 + 6 = 19 12 + 3 = 15 + 7 = 14 8. 7 + 6 + 2 = 15 7 Add. We can add in any order and get the same sum. 7. 5 + 3 + 4 = 12 Circle the addends you will add first. 9. 5 + 8 + 5 = 18 10. 4 + 8 + 5 = 17 Write the new number sentence and solve. Then solve again, adding in a different order. 11. 8 + 3 + 8 = 19 12. 9 + 6 + 2 = 17 1. 8 + 7 + 2 = 17 8 + 7 + 2 = 17 13. 1 + 7 + 6 = 14 14. 6 + 4 + 9 = 19 10 + 7 = 17 15 + 2 = 17 2. 7 + 4 + 5 = 16 7 + 4 + 5 = 16 Write the number sentence. Solve. 11 + 5 = 16 9 + 7 = 16 15. Judy has 8 red buttons, 4 green buttons, and 3 purple buttons. 3. 1 + 8 + 9 = 18 1 + 8 + 9 = 18 How many buttons does Judy have? 9 + 9 = 18 10 + 8 = 18 8 + 4 + 3 = 15 Judy has 15 buttons. Chapter 1 Lesson 14 OA.2 Adding with Three Addends 29 30 Now let’s practice adding three numbers together. We can choosing which two numbers to add first can make it easier add the numbers in any order and get the same sum, but and faster for us to add all three together.Copyright © by SPOTS Educational Resources. All rights reserved. STUDENT TEACHER DIFFERENTIATED INSTRUCTION Divide the class into groups of three, and give each student Some students may need to review their basic facts. Have a blank sheet of paper and a die. Have each student in the students practice together in pairs, using Addition Dot group roll his/her die and then write the number sentence Cards 1-9. to add all three numbers. Have each student in the group solve the same equation, adding the numbers in the order CLOSING STATEMENT: he/she prefers. Then have the students take turns sharing What did we learn today in math class? in which order they solved the equation. Ask: What are Today we practiced adding three numbers together. some ways that can help us decide in which order to add the Tomorrow we will subtract from teen numbers. numbers when we’re adding three numbers together? [Elicit that we can: 1. try to make a ten; 2. look for doubles facts; or 3. add the largest numbers first.] 29

Chapter 1 Lesson 15: Subtracting from Teen Numbers INTRODUCTORY STATEMENT: II. Practice Copyright © by SPOTS Educational Resources. All rights reserved. So far we’ve subtracted with numbers that are less than ten. Today we will use that to subtract Write 17 – 5, and draw a number-sentence format underneath (see page 25 of the Student’s Edition). Ask: Which number from teen numbers. sentence that we know can help us solve this? [7 – 5] [Fill in the number-sentence format.] GOAL: Ask: What is 7 – 5? [2] [Fill in the difference.] If we know that Students will subtract single-digit numbers from teen 7 – 5 equals 2, then we know that 17 – 5 equals…? [12] [Fill in numbers. the difference: 12.] MATERIALS NEEDED: subtraction equation cards with equations learned in this lesson; blank sheets of Repeat as above with 15 – 4. paper III. Subtracting mentallyCommon Core Standard: CCSS2.OA.2 Now let’s try a challenge. [Write 19 – 6 = ___ on the board.] LESSON WARMUP Can you tell us the difference without having us write a helping number sentence? Just think of it in your head. What is the Review facts for fluency using the My Math Facts practice difference? [13] What number sentence did you think of to help booklet. you find the difference? [9 – 6 = 3] THINKING TRIGGER Repeat with 18 – 5. Write 17 – 6 on the board. Ask: How would you solve this IV. Counting back to subtract equation? Write 17 – 2 on the board. Ask: How much are we subtractingCONCEPT DEVELOPMENT here? [2] We are subtracting just 2. We can count back two to find the difference. We begin with 17. We take away one, and weI. Using a number sentence to help have 16; and we take away another one, and we’re left with 15. 17 – 2 = 15.Refer to the equation on the board from the Thinking Trigger:17 – 6. Next to it, write 7 – 6. Ask: What is the same about these Say: When we’re subtracting a small number, we can also counttwo number sentences? [they have the same number of ones] back to find the difference.What is different? [the first number sentence also has a ten]Let’s use what we know to help us solve 17 – 6. We know that Repeat with 19 – 3.7 – 6 is…? [1] And we know that 17 – 6 is similar, but it has aten. [Use Dot Cards to show the equations.] The differences Write 16 – 3. Ask: How would you solve this? Would you thinkare also similar, but the difference of the first number sentence of a helping number sentence, or would you count back? [Pointwill have a ten: If 7 – 6 = 1, then 17 – 6 = 11. 7 – 6 is our helping out that either way is correct, and solve the equation bothnumber sentence to solve 17 – 6. [Elicit how this is similar to ways.]what they did previously with teen addition, in lesson 9.]Write 15 – 3 and 5 – 3 on the board. Say: I am going to use Practice counting back from 19 to 11 with your class.what I know to help me solve this number sentence. [Point tothe equation 5 – 3.] I know that 5 – 3 equals…? [2] [Fill in the STUDENT TEACHERdifference.] I know that 15 – 3 is similar, but it also has a ten. If5 – 3 equals 2, then 15 – 3 equals…? [12]. [Use Dot Cards to Divide the class into pairs. Give each pair two sheets ofshow the equations.] paper and two teen subtraction flash cards. Have each of the partners write both equations on their papers and solve30 them, either by using helping number sentences to help them, or by counting back. Have the students explain their thinking processes to their partners. Ask: What are some things we can do to help us subtract from a teen number? [Elicit that we can think of a number sentence to help, or we can count back to find the difference.]

Using the Book: pages 31-32 Subtracting from Teen Numbers Subtract. Subtract. 1. 8 2. 18 3. 6 4. 16 5. 7 6. 17 1. 2. 3. 4. –4 – 4 –5 – 5 –3 – 3 15 – 3 = 12 19 – 6 = 13 18 – 7 = 11 17 – 2 = 15 4 14 1 11 4 14 5. 6. 7. 8. 16 – 5 = 11 17 – 4 = 13 19 – 8 = 11 18 – 6 = 12 7. 9 8. 19 9. 4 10. 14 11. 5 12. 15 9. 10. 11. 12. –4 – 4 –3 – 3 –4 – 4 15 – 5 = 10 16 – 4 = 12 18 – 5 = 13 19 – 3 = 16 5 15 1 11 1 11 Write the number sentence that will help you solve the exercise. 13. 14. 15. 16. Solve. 14 – 2 = 12 19 – 4 = 15 17 – 5 = 12 16 – 1 = 15 13. 18 – 6 = 12 14. 17 – 4 = 13 Fill in the math puzzle and write the number sentence. Use a for the unknown number. Solve. 8 –6 = 2 7 – 4= 3 18 17.Boris has 18 yo-yos. 4 yo-yos are glow-in-the-dark. The rest are not glow-in-the-dark. Whole How many yo-yos are not glow-in-the-dark? 15. 19 – 5 = 14 16. 18 – 5 = 13 Number sentence: 18 – 4 = 14 4 14 14 yo-yos are not glow-in-the-dark. Part Part 9 –5 = 4 8 –5 = 3 18. There are 15 children in the yard. 15 17. 19 – 7 = 12 18. 17 – 6 = 11 4 are playing with sidewalk chalk. The rest are playing jump rope. Whole 9 –7 = 2 7 –6 = 1 How many children are playing jump rope? 4PaPrat rt 11PaPrat rt Number sentence: 15 – 4 = 11 Chapter 1 Lesson 15 OA2 Subtracting from Teen Numbers 31 11 children are playing jump rope. 32 Now let’s practice subtracting from teen numbers, using a helping number sentence to help us, or counting back to find the difference.Copyright © by SPOTS Educational Resources. All rights reserved. DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Some students may confuse the tens place and the ones What did we learn today in math class? Today place when the numbers are not lined up vertically. To help we subtracted from teen numbers. We used Dot Cards them keep track of place value, suggest that they highlight the ones place of each number in one color and the tens and thought of number sentences that help us. place in another color. Tomorrow we will subtract in two steps. 31

Chapter 1 Lesson 16: Subtracting in Two Steps INTRODUCTORY STATEMENT: In the same way, show 14 – 6: Cross off all the dots on the Yesterday we subtracted ones from teen numbers. ones side, then cross off two more dots from the tens side,Today we will subtract more than the ones that there and discuss what was done: First we crossed off four dots to getare in the teen number. We will subtract in two steps. to the ten, and then we crossed off two more dots from the tens side to get the difference. GOAL: Refer to the equation from the Thinking Trigger: 12 – 4. Ask: Students will subtract from teen numbers in two steps. How do you think we should show this equation with Dot Cards? MATERIALS NEEDED: Dot Cards [Accept answers; then first cross off all the ones, and cross off two dots from the ten side to get the difference of 8.]Common Core Standard: CCSS2.OA.2 II. Writing break-apart numbers LESSON WARMUP Ask: Do you remember our break-apart numbers from addition? Review facts for fluency using the My Math Facts We wrote what numbers we thought of when we added. Let’s practice booklet. write the break-apart numbers for these subtraction problems that we just did. [Point to 13 – 4 = 9.] How did we subtract? THINKING TRIGGER First we crossed off [Point to the three dots.] three to get to ten, and then we crossed off another one from the ten. Instead of crossing off four dots, we thought of crossing off three and then one. Our break-apart numbers are 3 and 1. [Draw spaces for the break-apart numbers, and fill them in accordingly.] Repeat for 14 – 6 and 12 – 4. Write 12 - 4 = ___ on the board, and place Dot Card-12 III. Adding by counting on Copyright © by SPOTS Educational Resources. All rights reserved. next to it. Ask: How can we show this on the Dot Card? Which dots should we cross off? On the board, write 17 – 8 = ___ in a break-apart number- sentence format. Ask the class to tell you how to show itCONCEPT DEVELOPMENT using Dot Cards: Show 17, cross off seven dots to get to 10, and then cross off one more. Fill in the break-apart numbers,I. Subtracting with Dot Cards and write the difference.Place Dot Card –13 on the board, and next to it write 13 – In the same way, solve 13 – 6, 15 – 6, 11 – 3, and 12 – 5. For4 = ___. Read the equation and say: We need to subtract 4. each equation, have students tell you how to show theCan we cross off all four dots from only the ones side? [No, we number sentence on a Dot Card and what the break-aparthave only three dots on the ones side.] How can we show numbers are.this number sentence? [Discuss students’ suggestions. Thenexplain:] We need to subtract more than the ones we have; we STUDENT TEACHERneed to cross off dots on both sides. First we cross off all thedots on the ones side. Let’s cross off the three ones. [Cross them On the board, write 16 – 7, 14 – 6, and 13 – 4. Have studentsoff.] Are we done? [no] Why not? [We need to subtract 4, and show them with Dot Cards and fill in the break-apartwe’ve crossed off only 3.] How many more do we need to cross numbers. Ask: What steps did you follow when youoff? [1] We need to cross off one more dot from the tens side. subtracted more than the ones that there were in the teen[Cross off one dot from the ten.] What is the difference? [9] number? [Elicit that they first had to cross off all the ones to[Write the difference.] We subtracted 4 in two steps: First we get ten, and then they crossed off the rest of the numbercrossed off the three dots on the ones side, and then we crossed from the ten, to find the difference.]off one more dot from the ten.32

Using the Book: pages 33-34 Subtracting in Two StXepxsx When we subtract more than the ones Cross off the dots you need to subtract. we have, we subtract in two steps. Fill in the break-apart numbers and write the difference. 1. 2. 3. First we subtract all the ones and get to ten. 155 – 6 = 19 Then we subtract the rest from the ten to get to ten the rest to find the difference. We break apart the 6. 5 and 1 are the break-apart numbers. Cross off the dots you need to subtract. 16 – 7 = 9 14 – 6 = 8 13 – 4 = 9 Fill in the break-apart numbers and write the difference. 61 42 31 to get to ten the rest to get to ten the rest to get to ten the rest 1. 2. 3. 4. 5. 6. 15 - 7 = 8 14 - 5 = 9 11 - 4 = 7 133 – 5 = 8 155 – 6 = 9 133 – 6= 7 52 41 13 2 1 3 to get to ten the rest to get to ten the rest to get to ten the rest to get to ten the rest to get to ten the rest to get to ten the rest 4. 5. 6. Fill in the math puzzle and write the number sentence. Use a for the unknown number. Solve. 12 - 4 = 8 11 - 5 = 6 12 - 5 = 7 7. There were 16 apples in a basket. 16 7 apples were sold. 2 2 1 4 2 3 How many apples are in the basket now? Whole to get to ten the rest to get to ten the rest to get to ten the rest Number sentence: 16 – 7 = 9 79 There are ___9___ apples are in the basket. Part Part 34 Chapter 1 Lesson 16 OA.2 Subtracting in Two Steps 33 Now let’s practice subtracting more than the ones that and get ten, then we’ll subtract the rest from the ten, to get there are in a teen number: First we’ll subtract all the ones the difference.Copyright © by SPOTS Educational Resources. All rights reserved. DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Some students may get confused about which way to What did we learn today in math class? break apart a number. Explain that they can always look Today we solved subtraction sentences in two steps. at the number of ones or the number of dots on the ones We used Dot Cards and wrote break-apart numbers. side, and write that number down as the first break-apart number. They can then count up to the number to deter- Tomorrow we will practice this more. mine what “the rest” is. 33

Chapter 1 Lesson 17: Practice: Subtracting in Two Steps INTRODUCTORY STATEMENT: [Write 15 – 7, and solve as above, without using Dot Cards. Copyright © by SPOTS Educational Resources. All rights reserved. Yesterday we subtracted from teen numbers. Today Fill in the break-apart numbers.] we will practice this more. II. Subtracting with the difference of ten as an aid GOAL: Write 14 – 4 on the board, and place Dot Card-14 next to Students will practice subtracting from teen numbers in it. Read the number sentence and ask: Can we solve this by two steps. crossing off dots on only the ones side? [yes] [Cross off the 4 MATERIALS NEEDED: Dot Cards; blank sheets of ones, and write the difference. Under that equation write 14 paper – 5. Read the number sentence and ask:] Can we subtract 5 by crossing off dots on only the ones side? [no] What do we need toCommon Core Standard: CCSS2.NBT.8 do? [cross off dots from both sides] First we cross off the ones to get to ten, and then we cross off another dot from the ten. LESSON WARMUP [Refer to the same Dot Card.] We already crossed off the 4 ones when we solved 14 – 4. Now, to solve 14 – 5, we just need to cross Review facts for fluency using the My Math Facts off another dot from the ten. [Cross off one dot from the ten.] practice booklet. What is the difference? [9] 14 – 4 = 10. For 14 – 5 we subtracted 1 more. The difference is 9. [In the same way, solve 15 – 5 and THINKING TRIGGER 15 – 6.] How do we subtract from a teen number when we need to Write 12 – 2 on the board, and place Dot Card-12 next to subtract more than the ones that there are in the number? it. Read the number sentence and ask: Can we subtract 2 by crossing off dots on only the ones side? [yes] [Solve 12 – 2.CONCEPT DEVELOPMENT Cross off the 2 ones, and write the difference. Write 12 – 4 underneath. Read the number sentence and ask:] Can weI. Subtracting in two steps subtract 4 by crossing off dots on only the ones side? [no] What do we need to do? [cross off dots from both sides] [Refer toWrite 13 – 4 on the board, and place Dot Card-13 next to the the same Dot Card.] We already crossed off the 2 ones whenequation. Have students tell you how to solve the equation we solved 12 – 2. Now, to solve 12 – 4, we just need to cross offusing the Dot Card. Remind them that when we subtract another two dots from the ten. [Cross off two dots from the tenmore than the ones that there are in the teen number, we side.] How many are left? What’s the difference? [8] [Write thefirst subtract all the ones to get to ten, and then we subtract difference.] 12 – 2 = 10. For 12 – 4 we subtract two more. Thethe rest of the number from the ten to get the difference. difference is 8. [In the same way, solve 13 – 3 and 13 – 5.]Add spaces for the break-apart numbers and say: Now let’swrite how we broke apart the 4 that we needed to subtract. How III. Subtracting without using Dot Cardsmuch did we cross off at first (from the ones side)? [3] [Fill in 3.]How much more did we need to subtract from the ten? [1] [Fill Write 17 – 7 = ___ on the board. Ask a student to tell what thein 1.] The break-apart numbers are 3 and 1. difference is, and fill it in. Write 17 – 8 = ___. Say: Let’s try toNow let’s do this without the Dot Cards. [Write 16 – 7 = ___ solve this without using Dot Cards. When we subtract 7, we areon the board.] Let’s see: We are subtracting more than the ones left with 10. When we subtract 8, we need to subtract one more.that there are in 16. How should we do this? [Allow students to What is the difference? [9]make suggestions.] We will subtract in two steps. First we needto subtract all the ones to get to ten. How many ones? [6] [Draw Repeat this with 14 – 4 and 14 – 6. Write 14 – 4 = ___ on thespaces for the break-apart numbers. Fill in 6.] We need to board. Ask a student to tell what the difference is, and fill it in.subtract 7 altogether. How much more do we need to subtract Write 14 – 6. Say: Again, let’s try to find the difference withoutto get the difference? [1] [Fill in 1.] What is our difference? [9] using Dot Cards. When we subtract 4, we are left with only the ten. When we subtract 6, we need to subtract two more from the ten. What is the difference? [8] [In the same way, solve 13 – 3, 13 – 4, and 13 – 5. Stress how knowing 13 – 3 helps us solve 13 – 4 and 13 – 5.]34

Using the Book: pages 35-36 Practice: Subtracting in Two Steps Subtract. 3. 12 – 2 = 10 4. 12 – 4 = 8 Cross off the dots you need to subtract. 1. 14 – 4 = 10 Fill in the break-apart numbers and write the difference. 2. 14 – 5 = 9 7. 13 – 3 = 10 8. 13 – 5 = 8 1. 2. 3. 5. 15 – 5 = 10 6. 15 – 6 = 9 14 – 6 = 8 12 – 5 = 7 13 – 6 = 7 42 23 33 to get to ten the rest to get to ten the rest to get to ten the rest Subtract. 4. 5. 6. 9. 10. 11. 12. 13. 14. 17 17 15 15 13 13 –7 –8 –5 –7 –3 –4 10 10 10 9 8 9 13 – 5 = 8 15 – 6 = 9 11 – 4 = 7 15. 16. 17. 18. 19. 20. 32 51 13 to get to ten the rest to get to ten the rest to get to ten the rest 16 16 14 14 12 12 –6 –7 –4 –6 –2 –3 10 10 10 9 8 9 LET’S WRITE! Practice. 22. 23. 24. 25. 21. Look at exercise number 1. Explain how you solved 14 – 6. 13 12 12 19 E_x_p_l_a_n_a_t_io_n_s__w_il_l_v_a_ry_._P_o_s_s_ib_l_e_e_x_p_l_a_n_a_t_io_n_:_I_b_r_o_k_e_6__in_t_o_4__+__2_. ____ 11 –6 –5 –6 –9 I_s_u_b_t_r_a_c_te_d__1_4_–__4_=__1_0_a_n_d__th__e_n_1_0__–_2_=__8_._____________________ –5 10 7 7 6 _________________________________________________________ 6 Chapter 1 Lesson 17 OA.2 Practice: Subtracting in Two Steps 35 36 Now let’s practice subtracting from teen numbers. When we get to ten, then we subtract the rest from the ten to find the subtract more than the ones that there are in a teen number, difference. we subtract in two steps: First we subtract all the ones andCopyright © by SPOTS Educational Resources. All rights reserved. STUDENT TEACHER the equation on a Dot Card; 3) under the equation draw spaces for the break-apart numbers, and fill them in. Ask: Have the students work in pairs. Give each pair a blank What steps did you use to subtract more than the amount of sheet of paper, and have them divide the paper in half. Write ones that there were in the teen number? [Elicit that first they the following equations on the board: 12 - 4, 13 - 5, 15 - 6, subtracted all the ones to get to ten, then they subtracted 12 - 5, 14 - 6, 11 - 5, and 13 - 6. Ask each pair to choose two the rest of the number from the ten to find the difference.] problems to solve, and to take turns filling in the parts for each equation as follows: 1) write the equation; 2) model DIFFERENTIATED INSTRUCTION CLOSING STATEMENT: Some students may have trouble with subtracting in What did we learn today in math class? two steps. Help them sharpen this skill by practicing Today we solved subtraction sentences in two steps. with facts that equal 10 (e.g., 14 – 4 = 10 and 16 – 6 = 10). Also, check and remediate student fluency level Tomorrow we will work with number lines. with the 10 – ___ facts. 35

Chapter 1 Lesson 18: Using the Number Line to Subtract INTRODUCTORY STATEMENT: number does he need to start? [17] Where do we write the 17?Yesterday we subtracted from teen numbers by using [on the right side] [Fill in the number line, as above, as you go along.] How many does Bunny need to jump? [7] On what Dot Cards. Today we will use number lines. number did he land? [10] How much is 17 – 7? [10] [Write the difference in the equation, and read the equation.] In the GOAL: same way, solve 15 – 5. Students will subtract from teen numbers using an III. Subtracting from teen numbers with open number line. two jumps MATERIALS NEEDED: “Bunny”: a small toy rabbit or rabbit cutout On the board, write 14 – 6 = ___, and place Dot Card-14 next to it. Review the process of subtracting all the ones andCommon Core Standard: CCSS2.NBT.8 then subtracting the rest from the ten. Draw spaces for the break-apart numbers, and ask the class help you fill them LESSON WARMUP in. Fill in the difference. Draw an open number line next to the equation. Ask the class: Bunny wants to subtract on the Review facts for fluency using the My Math Facts number line. Let’s think: How many jumps will he make? [two practice booklet. jumps, to show the two steps] THINKING TRIGGER Let’s help Bunny solve this on the number line. With which Copyright © by SPOTS Educational Resources. All rights reserved. number should we start? [14] Where should I write the 14? [at the Draw an open number line on the board, and write end, on the right side] How did we solve this number sentence? 14 – 5 = ___. Ask: How many jumps on the number line do First we subtracted …? [4] and got to 10. Bunny will do the same. you think we need to make in order to show this number [Draw a jump from the 14 to the 10, and write in –4.] Where sentence? did we end up? [10] [Write the landing number 10.] Then we took away another 2 and got to 8. Bunny will do this too. [DrawCONCEPT DEVELOPMENT a jump of 2, and fill in –2.] On what number did Bunny land? [8] [Write the difference (8) at the end of the second jump.]I. Subtracting from 10 with one jump 14 – 6 = 8. First we made a jump of 4 and got to ten, and then we made a jump of 2 to get to the difference, 8. When we firstDraw an open number line on the board. Display the toy subtract all the ones and get ten, and then we subtract the restrabbit and ask: Who can tell us about Bunny? How does Bunny from the ten, it’s easy to find the difference. How many jumpsjump? [a few numbers at a time] did we make? [2] Bunny jumped 6 in two jumps: a jump of 4 and a jump of 2 – the same as the break-apart numbers.Today Bunny will subtract. [Write 10 – 3 = ___ next to thenumber line.] Do you remember how to subtract on the number Repeat the process with 13 – 5 and 16 – 7. For each, first solveline? On which side do we start? [at the end, on the right side] with the Dot Board and write the break-apart numbers, thenWhy? [because we are taking away] To what direction do we have Bunny show it on the number line, and summarize asjump? [back, to the beginning of the number line] [Write above. Each time, emphasize that first we subtract to get to10 on the far right side of the number line.] How many does 10, and then we subtract the rest of the number.Bunny need to jump? [3] [Show Bunny making a jump ofapproximately three spaces. Draw the jump. Write in –3.] To IV. Subtracting in two steps withoutwhat number did Bunny get? How much is 10 – 3? [7] [Write 7 visual aidsunder the landing point. Fill in the difference in the equation,and read it together.] Our number line shows 10 – 3 = 7. Write 12 - 5 on the board. Say: Now let’s do some subtraction in our heads. Can we take away 5 from only the ones? [no; inIn the same way, use Bunny to solve 10 – 4 on a number line. the number 12 there are only 2 ones] So let’s first subtract the 2 ones that there are, and we will be left with…? [10]II. Subtracting to equal 10 with one jump We need to subtract 5; we’ve subtracted only 2. How many more do we need to subtract from the 10? [3 more] Now let’sWrite 17 – 7 = ___ on the board, and draw an open numberline. Say: How will Bunny subtract on the number line? On what36

Using the Book: pages 37-38 Using the Number Line to Subtract We make 2 jumps back. Complete the number line. Write the difference. First we jump back to the ten. 1. Then we jump back the rest. 15 – 7 = –7 15 – 6 = 9 –6 –5 15 2. –1 12 – 4 = 8 9 10 15 Complete the number line. Write the difference. 3. 1. –5 –4 12 – 5 = 7 –3 –2 –2 –2 7 10 12 8 10 12 2. –6 –4 12 – 6 = 6 –4 –6 –2 14 – 6 = 8 –2 14 ON YOUR OWN! 6 10 12 8 10 4. 3. –6 –7 16 13 – 6 = 7 –1 Subtract. 16 – 7 = 9 9 10 5. 14 6. 13 7. 12 4. –6 –5 –5 887 –5 –4 8. 12 9. 11 10. 13 38 –3 –4 –4 14 – 5 = 9 –1 14 9 79 Lesson 18 OA.2 9 10 Chapter 1 Using the Number Line to Subtract 37 Now let’s practice subtracting on the number line. When we ten, we make two jumps: first a jump back for all the ones, to subtract from a teen number, and the difference is less than get to ten, then another jump for the rest.Copyright © by SPOTS Educational Resources. All rights reserved. subtract 3 more from the 10. We are left with…? [7] What is the DIFFERENTIATED INSTRUCTION difference? [7] 12 – 5 = 7. [Fill in the difference.] Some students may have trouble subtracting from teen In the same way, solve 15 - 7 and 11 - 4 together. numbers. Remind them of the various methods they have already explored when adding with a sum that is a teen STUDENT TEACHER number (i.e., they can think of Dot Cards, break-apart numbers, or number lines; they can also use the Dot Card Write the following equations on the board: 14 - 5, 13 - 6, 15 banner to help). - 6, 12 - 4, and 17 - 8. Divide the class into pairs. Give each student a blank sheet of paper. Have each pair choose one CLOSING STATEMENT: equation to solve. Have one partner solve the equation us- What did we learn today in math class? ing break-apart numbers, and have the other partner solve Today we used number lines to subtract. Tomorrow we it on an open number line. Then have the partners compare will review different ways to subtract, and each student their work; the break-apart numbers and the numbers of will decide which way is best for him/her. the jumps, and the differences, should be the same. Have the partners switch roles to solve another problem. Ask: 37 When we subtract from a teen number and the difference will be less than ten, how many jumps do we make on the number line? [two: one jump back for all the ones, to get to ten, and a second jump for the rest]

Chapter 1 Lesson 19: Choosing a Way to Subtract INTRODUCTORY STATEMENT: same today with subtraction. I want each of you to think about We’ve learned different ways to subtract from teen the different ways to subtract, and to decide which one you numbers. Today we will think about those ways and think works best for you. Remember, different students will have different ways that work best for them, and that is okay. decide which way works best for each of us. Hand out three sheets of paper to each student. Have students GOAL: draw an open number line on the first sheet of paper. Write 14 – 5 on the board. Have the students solve the problem Students will choose the method that they prefer when using the number line, and when they are done, have each of subtracting from teen numbers. them mark how long it took. (You can display a large digital MATERIALS NEEDED: sheets of paper; large timer, stopwatch, or you can flip numbered cards at an even pace, numbered cards, or numbered flip chart so that they can time themselves.) Tell the students to mark on their papers how long it took them to solve the equationCommon Core Standard: CCSS 2.OA.A.1 using the number line. LESSON WARMUP Write 14 – 6 on the board. Have the class solve the problem using break-apart numbers on the second sheet of paper, Review facts for fluency using the My Math Facts while you time them. Have them write on their papers how practice booklet. long it took them to solve it. THINKING TRIGGER Have students draw a blank double Dot Card on the third paper. Write 12 – 5 on the board, and have the class fill in the Dot Card to solve it while you time them. Write 16 - 7 on the board. Ask: What are some ways Ask them to think about which way was easiest for them and Copyright © by SPOTS Educational Resources. All rights reserved. we can solve this? [Show the different ways (Dot Card, which way was quickest. Point out that easiest and quickest number line, and break-apart numbers), but it is not are not always the same, and that all the methods are good necessary to solve the equation.] ones. You can repeat this activity.CONCEPT DEVELOPMENT Ask each student to write on a paper the method that is best for him or her. Collect the papers, and count the number ofI. Reviewing subtraction using Dot Cards students who preferred each method. See which method is the most popular and which is the least. Again, stress thatWrite 13 – 6 on the board. Have the class tell how to show it everyone has a method that works best for him or her.using Dot Cards. STUDENT TEACHERII. R eviewing subtraction using break-apart numbers Write 12 – 5 on the board. Have three students solve it, each using a different method. Ask: What are the different ways weWrite 12 – 4, and solve together with the class: Discuss how can use to solve subtraction problems? [Elicit that we can useto break apart the four (2, 2), draw spaces for the break-apart Dot Cards, a number line, or break-apart numbers.]numbers, and fill them in. Then write the difference.III. Reviewing subtraction using a number lineWrite 17 – 8 on the board. Have the class tell how to show iton a number line.IV. Choosing what works bestAsk: Do you remember how, a few days ago, you chose the wayto add teen numbers that works best for you? We will do the38

Using the Book: pages 39-40 Choosing a Way to Subtract Subtract. Which way works best for you? Circle the way that works best for you. Subtract. 14 – 6 = 1. 13 – 6 = 7 2. 14 – 7 = 7 I like to use 14 – 7 = 7 break-apart 13 – 6 = 7 numbers. 33 43 14 – 6 = 8 to get ten the rest to get ten the rest I like to 42 use the Dot Card. to get ten the rest I like to use –6 -4 –7 -3 the number -3 -3 line. 7 10 14 7 10 13 –6 –2 –4 8 10 14 Subtract. Circle the way that works best for you. Subtract. 3. 4. 5. 6. 7. 1. 13 – 5 = 8 2. 15 – 7 = 8 15 11 13 11 14 –7 –4 –4 –6 –5 8 7 9 5 9 133 – 5 = 8 155 – 7 = 8 Fill in the math puzzle and write the number sentence. 2 2 Use a for the unknown number. Solve. to get to ten the rest to get to ten the rest -5 -7 -2 8. Pat has 15 flowers. 8 flowers are in a vase. 15 The rest are in a basket. -3 -2 -5 15 How many flowers are in a basket? Whole 8 10 13 8 10 Number sentence: 15 – 8 = 7 87 ___7___ flowers are in a basket. Part Part Chapter 1 Lesson 19 OA.2 Choosing a Way to Subtract 39 40 Now let’s practice different ways of subtracting, using Review the page. Ask students to tell which method they Dot Cards, break-apart numbers, and number lines. used for each example. Remind students to use the method that works best for them.Copyright © by SPOTS Educational Resources. All rights reserved. CLOSING STATEMENT: What did we learn today in math class? Today we solved subtraction sentences using different ways: Dot Cards, break-apart numbers, and number lines. We thought about which way works best for us. Tomorrow we will learn about a different way to cross off the dots when we subtract a lot. 39

Chapter 1 Lesson 20: Subtracting a Lot from a Teen Number INTRODUCTORY STATEMENT: [Cross off nine dots from the tens side. Explain that there Until now, we’ve learned different ways to are dots left on both sides. Solve the equation and write the subtract from teen numbers. Today we will learn difference.] a quick way to subtract 10, 9, 8, and 7. III. Subtracting 8 with Dot Cards GOAL: Place Dot Card-12 on the board. Say: I want to take away 8. Eight is also a lot – it’s almost as much as ten, so I will cross off Students will subtract 10, 9, 8, and 7 from teen numbers eight dots from the tens side. [Cross off eight dots on the tens by crossing off dots from the tens side of the Dot Card. side, commenting that we cross off the dots in the pattern of MATERIALS NEEDED: three copies each of Dot Dot Card-8.] When we cross off eight from the tens side, there Cards-17 and -11 are two dots left on the tens side and two dots left on the ones side. There are four dots left: 12 – 8 = 4. [Write the numberCommon Core Standard: CCSS2.OA.A.1 sentence: 12 – 8 = 4.] LESSON WARMUP Write 13 – 8 on the board, and place Dot Card-13 next to it. Ask: From where should I cross off eight? [from the tens side] Review facts for fluency using the My Math Facts [Cross off eight dots from the tens side. Point out that there practice booklet. are dots left on both sides. Solve the number sentence and write the difference.] THINKING TRIGGER IV. Subtracting 7 with Dot Cards Copyright © by SPOTS Educational Resources. All rights reserved. Write 15 – 10, 19 – 10, and 13 – 10 on the board. Ask: Write 12 – 7 on the board. Say: Now I want to take away 7. Can you think of a quick way to subtract ten from a teen Seven is also a lot; so I will cross off seven dots from the tens number? side. [Cross off seven dots on the tens side, explaining that we cross off the dots in the pattern of Dot Card-7.] When weCONCEPT DEVELOPMENT cross off seven dots from the tens side, there are three dots left on the tens side and two dots left on the ones side. There are fiveI. Subtracting ten using Dot Cards dots left in all. [Fill in the difference.]Show Teen Dot Cards-13 and -15. For each one, cross off the Write 13 – 7 on the board, and place Dot Card-13 next to it.tens side and write the equation together with the class. Ask: From where should I cross off seven? [from the tens side]Explain that you are taking away the ten and have only the [Cross off seven dots from the tens side. Point out that thereones left. are dots left on both sides. Solve the number sentence and write the difference.]II. Subtracting 9 with Dot Cards V. Practicing the skillPlace Dot Card-12 on the board. Say: I want to take away 9.Nine is a lot – it’s almost as much as ten, so I will cross off nine Place three copies of Dot Card-17 on the board, and write thedots from the tens side. [Cross off nine dots on the tens side equations 17 – 10, 17 – 9, and 17 – 8 on the board. For each(as in page 43 in the Student’s Edition).] When we cross off equation, ask the students to tell you how to cross off thethe nine dots, we make sure that the crossed-off dots follow the dots and what the difference is.pattern of Dot Card-9. Now we have dots left on both sides:There’s one dot left on the tens side, and there are two dots left In the same way, place three copies of Dot Card-11 on theon the ones side. There are three dots left in all: 12 – 9 = 3. [Write board, and write the equations 11 – 9, 11 – 8, and 11 – 7, crossthe number sentence: 12 – 9 = 3.] off the dots, and write the differences.Write 13 – 9 on the board, and place Dot Card-13 next to it.Ask: From where should I cross off nine? [from the tens side] VI. Subtracting using the ten as an aid40 Clear the board. Write 13 – 10 = ___ on the board. Ask a student to tell what the difference is, and fill it in. Write 13 – 9 = ___. Say: Let’s try to solve this without using Dot Cards. Let’s think about it. When we take away ten, we are left with only the ones. When we take away 9, we have 1 left on the tens side and also the 3 ones; together we have 4 left: 13 – 9 = 4.

Using the Book: Complete pages 41-42. Subtracting a Lot from a Teen Number Subtract. You can use the Dot Cards to help. When we subtract a lot, we can 1. 4 3. 7 5. 8 cross off dots only on the tens side 14 – 10 = 17 – 10 = 18 – 10 = and see how many dots are left on both sides. 13 – 8 = 5 2. 5 4. 8 6. 9 14 – 9 = 17 – 9 = 18 – 9 = Cross off the dots you need to subtract. Write the difference. 7. 2 9. 3 11. 1 1. 2. 3. 12 – 10 = 13 – 10 = 11 – 10 = 8. 3 10. 5 12. 2 12 – 9 = 13 – 8 = 11 – 9 = 16 – 9 = 7 14 – 8 = 6 18 – 10 = 8 Practice. 4. 5. 6. 13. 14. 15. 16. 17. 18. 16 11 14 11 13 12 –10 – 8 –8 –7 –7 –8 63 6 4 6 4 11 – 7 = 4 13 – 9 = 4 12 – 7 = 5 LET’S WRITE! 7. 8. 9. Look at exercise number 18. Explain how you solved 12 – 8. _E_xp__la_n_a_t_io_n_s__w_i_ll_v_a_r_y._P_o_s_s_ib__le__e_xp__la_n_a_t_io_n_:_______________________ _I s_u_b__tr_a_c_te_d__8_f_r_o_m__th__e_t_e_n_s_s_id_e_s_._Th__is_l_e_ft_2__o_n__th_e__te_n_s__s_id_e__an__d_2 more on the ones side. That made 4. 15 – 9 = 6 13 – 7 = 6 16 – 8 = 8 Chapter 1 Lesson 20 OA.2 Subtracting a Lot from a Teen Number 41 42 Now let’s practice subtracting by crossing off the dots from the tens side. Write 13 – 8 = ___ on the board. Say: Let’s try to solve this DIFFERENTIATED INSTRUCTION without using Dot Cards. When we take away 10, we are left with only 3 ones. When we take away 8, we have 2 left on the Since this is a new method, different from the break-apart tens side and also the 3 ones; we have 5 left in all: 13 – 8 = 5. [Fill method, students may get confused about how to cross in the difference.] off the dots. Display Dot Cards-7, -8, and -9. The dots that they cross off should match the setup of those Dot Cards. Write 16 – 9, 13 – 8, 14 – 9, and 15 – 8. Solve each as above, by thinking of subtracting ten as an aid.Copyright © by SPOTS Educational Resources. All rights reserved. STUDENT TEACHER CLOSING STATEMENT: What did we learn today in math class? Have students work in pairs, modeling and solving two teen Today we subtracted 10, 9, 8, and 7 from teen numbers, subtraction problems: 12 – 8 and 12 – 3. Ask: How are the by crossing off the dots from the tens side , and we methods you used to solve these two problems different? [Elicit reviewed subtracting by just thinking about Dot Cards. that when subtracting a lot, we cross off the dots from the Tomorrow we will practice both ways of subtracting – tens side, then we see how many dots are left on tens side subtracting a lot and subtracting a little. and how many are on the ones side to find the difference. When subtracting a number that is a little more than the 41 ones we have, first we subtract all the ones, then we sub- tract the rest from the ten.]

Chapter 1 Lesson 21: Mixed Practice: Teen Subtraction INTRODUCTORY STATEMENT: II. Subtracting 7 Copyright © by SPOTS Educational Resources. All rights reserved.We’ve learned the different ways we can use Dot Cards to subtract from teen numbers. Today we will review Write 12 – 7 and 11 – 7 on the board. Say: Yesterday, when we subtracted 7 from a teen number, we crossed off dots from the them and think about how we cross off the dots. tens side to find the difference. This works well when we subtract 7 from a teen number that doesn’t have many ones, like 11 or GOAL: 12. [Solve the equations on the board, in each case crossing off seven from the tens side of a Dot Card.] Students will review subtraction from teen numbers MATERIALS NEEDED: copies of Teen Dot Cards; small Write 16 – 7 on the board. Say: 16 has lots of ones – almost cards for each student as many as the number we are subtracting from it. When we subtract 7 from a larger teen number, like 16, it may be easier toCommon Core Standard: CCSS 2.OA.A.1 think of subtracting in two steps – crossing off all the dots on the ones side of a Dot Card, then crossing off the rest from the tens LESSON WARMUP side. [Solve the equation using a Dot Card. Explain how you are crossing off all six dots on the ones side, and one more Review facts for fluency using the My Math Facts dot on the tens side, so there are nine dots left. Write in the practice booklet. difference.] THINKING TRIGGER When we subtract 7 from a larger teen number, we can decide how we’d like to find the difference: We can cross off seven dots Display a blank Teen Dot Board. Ask: What are different from the tens side, just as we do when we subtract 7 from a ways we cross off the dots when we subtract? smaller teen number, such as 11 or 12. Or we can first cross off all the ones and then cross off the rest from the tens side. EitherCONCEPT DEVELOPMENT way, we’ll get the correct answer! Which way do you think would be easier for you? [Allow students explain which method theyI. Crossing off only from the tens side or in like best and why.] two steps III. Mixed PracticePlace Dot Card-12 on the board. Write three equations: 12–10, 12 – 9, and 12 – 8. Say: We’ve just reviewed subtracting a Place Dot Card-15 on the board, and write 15 – 2, 15 – 5, andlot. From where do we cross off the dots when we subtract a lot? 15 – 7. Read the equations and ask: In which number sentence[from the tens side] [For each equation, cross off dots and will the answer be less than ten? [15 – 7] How do you know?solve.] [because we’re taking away more than the amount of onesWrite the equations 12 – 3 and 12 – 4 on the board. Ask: Are we have] [Solve all three equations. Repeat with 17 – 5, 17 –we subtracting a little or a lot? [a little] Who remembers how we 9, and 17 – 7, and with other, similar sets of equations.]cross off dots for these equations? [cross off first from the onesside and then from the tens side] We subtract in two steps. STUDENT TEACHERFirst we subtract all the ones, then we subtract the rest from theten. We cross off from both sides. [Cross off dots to solve each Have the students work in pairs. Give each pair a set of 10equation.] cards. Have them write a teen subtraction sentence on eachWhen we subtract a lot, such as 10, 9, or 8, from a teen number, card. Ask them to divide their cards into two piles, accordingwe subtract only from the tens side. When we subtract a little, to how they would cross off the dots (on both sides, or onbut more than the ones we have, we subtract in two steps. only the tens side). Ask: How do you decide from which sideFirst we subtract all the ones, and then we subtract the rest to cross off the dots? [Elicit that when we subtract a lot, wefrom the tens side. cross off dots from the tens side; when we subtract a num- ber that is a little more than the ones we have, we cross off42 first from the ones side and then from the tens side; when, for example, when we subtract 7 from a larger teen number, we can either cross off the dots from the tens side, or we can first cross off all the ones and then cross off the rest from the tens side.]

Using the Book: pages 43-44 Mixed Practice: Teen Subtraction Decide how to subtract. Cross off the dots and write the difference. When we subtract more than the ones there are, 1. 15 2. 15 3. 15 we can subtract in two steps. –6 –8 –9 13 13 9 76 –4 –8 95 First we subtract all the ones, and then or we can subtract 4. 12 5. 12 6. 12 we subtract the rest from the tens side, only on the tens side. – 10 –6 –9 2 6 3 Decide how to subtract. Cross off the dots and write the difference. Subtract. 1. 14 2. 14 3. 14 7. 16 8. 16 9. 13 10. 14 11. 13 –5 –9 –8 –6 –7 –4 –5 –6 9 5 6 9 997 10 4. 12 5. 12 6. 12 12. 17 13. 17 14. 12 15. 13 16. 15 –5 –8 –3 – 10 –9 –8 –7 –9 7 4 9 7 8 4 6 6 7. 11 8. 11 9. 11 Fill in the math puzzle and write the number sentence. –9 –4 –6 Use a for the unknown number. Solve. 2 7 5 17. There were 14 ladybugs on a log. 14 10. 13 11. 13 12. 13 7 of them crawled away. –5 – 10 –7 How many ladybugs are on the log now? Whole 8 3 6 Number sentence: 14 – 7 = 7 77 ___7___ ladybugs are on the log now. Part Part Chapter 1 Lesson 21 OA.2 Mixed Practice: Teen Subtraction 43 44 Now let’s practice deciding from where we will cross off dots from the ten. When we subtract a lot, we subtract from only the when we subtract from teen numbers. When we subtract a tens side. When we subtract 7, we can decide for ourselves from little, we first subtract the ones, and then we subtract the rest which side (or sides) to subtract.Copyright © by SPOTS Educational Resources. All rights reserved. CLOSING STATEMENT: What did we learn today in math class? Today we thought about how we cross of the dots when we subtract. Tomorrow we will review everything we learned in this chapter. 43

Chapter 1 Lesson 22: End-of-Chapter Review INTRODUCTORY STATEMENT: what number to begin (9), how many to jump to get to ten We’ve reached the last lesson in this chapter! (1), how many more to jump to the sum (7), and what the sumToday we will review all the skills we’ve worked with in is (17). this chapter. In the same way, solve 8 + 6 on a number line. GOAL: IV. Adding three addends Students will review concepts and skills learned in this Write 8 + 4 + 2 = ___ on the board. Ask students to tell which chapter. two numbers they would add first, and circle them. Discuss the options for choosing the two numbers (equal ten; doublesCommon Core Standard: CCSS 2.OA.A.1, CCSS 2.OA.B.2 facts; largest numbers; in any order). Solve the equation. Do the same for 2 + 9 + 7.LESSON WARMUP V. Subtracting from teen numbers in two stepsReview facts for fluency using the My Math Factspractice booklet. Write 16 – 7 = ___ on the board. Have students tell how to solve it using a Dot Card. Discuss first taking away the ones toTHINKING TRIGGER get to 10, and then subtracting the rest to find the difference. Add spaces for the break-apart numbers, and fill them in. Do the same for 14 – 6 and 11 – 5. Look through your booklets. Can you tell us some of the VI. Subtracting on a number line Copyright © by SPOTS Educational Resources. All rights reserved. things we’ve learned and reviewed? [List them on the board as students say them. Mention and add to the list Next to 11 – 5 draw an open number line. Have the students other skills reviewed in the chapter that students did tell you how to show the equation on the number line: with not mention.] what number to begin (11), at which side to begin (at the end of the right side), how many to jump back to get to ten (1),CONCEPT DEVELOPMENT how many more to jump to the difference (4), and what the difference is (6).I. Adding and subtracting to ten In the same way, solve 13 – 7 on a number line.On the board, write 3 + 4 = ___, 7 + 2 = ___, 8 - 5 = ___, and9 – 2 = ___. Have students tell how to solve the equations VII. Subtracting a lot(count on, count back). Fill in the sums and differences. Write 16 – 10, and have students tell how to solve it (byII. Adding with teen sums in two steps subtracting the ten). In the same way, solve 14 – 9 and 11 – 8 (in each, we cross off only on the tens side).Write 7 + 5 = ___ on the board, and place the 7+ Dot Boardnext to it. Have students tell how to solve it by making a ten STUDENT TEACHERand adding the rest. Add spaces for the break-apart numbers,and fill them in. Choose skills that need extra review. Write some examplesDo the same for 8 + 6 and 9 + 8. of these skills on the board, and for each example have a student solve and explain his/her thinking.III. Adding on a number lineNext to 9 + 8, draw an open number line. Have the studentstell you how to show the equation on the number line: with44

Using the Book: pages 45-46 End-of-Chapter RevieXwxx Write three possible pairs of addends. XCxoxlor the dots and draw an arrow to make a ten. Abby has six folders. Fill in the break-apart numbers and write the sum. Some of the folders are flowered and some of the folders have stripes. 19 + 6 = 15 3 12 1. 6 2. 6 3. 6 5 2 Whole Whole Whole to get to ten the rest to get to ten 51 42 33 the rest Part Part Part Part Part Part Cross off the dots you need to subtract. Fill in the break-apart numbers and write the difference. 3. 4. 6 = 5 + 1 6 = 4 + 2 6= 3 + 3 Fill in the math puzzle and write the number sentence. 14 – 5 = 9 133 – 6 = 7 Use a for the unknown number. Solve. 41 3 to get to ten the rest to get to ten the rest 4. Aliza has 8 gel pens. 8 2 gel pens do not have a cover. How many gel pens have a cover? Whole Circle the addends you will add first. Number sentence: 8 – 2 = 6 2 Write the new number sentence and solve. ___6___ gel pens have a cover. Part Part 5. 3 + 6 + 5 = 14 6. 4 + 4 + 3 = 11 9 + 5 = 14 8 + 3 = 11 Decide how to subtract. Cross off the dots and write the difference. 5. There are 9 cherries in a bowl. 9 5 of the cherries are red. 7. 16 8. 16 9. 16 The rest of the cherries are white. Whole –7 –9 –8 How many of the cherries are white? 5 9 78 Number sentence: 9 – 5 = 4 Part Part There are __4____ white cherries. Chapter 21 ELensds-oonf ChapteCrCSRS1e.0vA.1iew Xxx. O A.2 4455 46 Now let’s practice what we’ve learned in this chapter. CLOSING STATEMENT: What did we learn today in math class? Today we reviewed all the skills we’ve worked with in this chapter. This is the last lesson of this chapter.Copyright © by SPOTS Educational Resources. All rights reserved. 45



Chapter 2 IntroductionIn Chapter 2, students go deeper in their exploration of two-digit numbers byexamining the concept of place value. Two-digit numbers are represented inthis chapter by simply adding Dot Cards-10 onto the left side of the number-representation cards. For example, a Dot Card representation of 25 wouldsimply add one more Dot Card-10 to the left of the representation of 15 (or twomore cards to the left of the representation of 5.) In this chapter students arefamiliarized with the standard way of representing a multi-digit number goingfrom left to right in decreasing order of place value.Number concepts that are an outgrowth of this exposure to place value,and that continue to develop students’ numeracy skills, are examined in thischapter. These concepts include comparing two-digit numbers, breakingdown a number into its expanded form, finding ten more or ten less thana two-digit number by incrementing or decrementing the tens digit, andcounting on by tens from any one- or two-digit number. Number charts arealso explored within this chapter in order to elucidate the patterns inherentin the place-value system.Money skills are explored in this chapter as well; these skills are introducedgradually throughout the chapter, to enable the students to internalize them.In the final lessons of the chapter, students examine different strategies forcounting mixed collections of coins, and they investigate ways to make equalcollections of coins for a given set. In this section students employ these skillsto determine whether or not there is enough money in a collection of coinsto buy a pictured item – a real-world application that is relevant to their livesat this stage, and yet another way that they can appreciate the gift of theirexpanding mathematical knowledge.

Chapter 2 Lesson 1: Representing Two-Digit Numbers INTRODUCTORY STATEMENT: this show? [7] [Show all three Dot Cards.] What number does In the last chapter, we reviewed how to add and this show? [27]subtract through ten, and how to add with teen sums and subtract from teen sums. Today we will review Ask students why they think Dot Cards are arranged with the tens on the left. Brainstorm with students about other different ways to show two-digit numbers. ways to arrange them. Encourage students to see that the Dot Cards are arranged so that we can quickly recognize the GOAL: number without having to count the dots. Students will learn to represent two-digit numbers by III. Showing two-digit numbers another way writing the number of tens and the number of ones. MATERIALS NEEDED: Dot Cards, model dimes, and Ask for four volunteers to come to the front of the room and model pennies face the class. Ask: What do we have on our hands that can show ten? [Fingers] [Ask students how the first volunteer,Common Core Standard: CCSS2.NBT.1, CCSS2.MD.8 who is standing on the students’ left, can show ten. (He/ she can hold up all ten fingers.) Ask the class how the four LESSON WARM-UP volunteers can show 36. Have the students discuss ideas. Students might discover that there is more than one way to Review facts for fluency using the My Math Facts show 36. Point out that everyone will see the number quickly practice booklet. if the first three students hold up ten fingers, and the fourth student holds up six fingers.] THINKING TRIGGER IV. Dimes and Pennies You know that you can show the number ten using dots on a Dot Card. What is another way to show ten? Have you Put a dime on the board. Ask: What is the name of this coin? [a ever bought something that comes in a box of ten? dime] What is the value of a dime? [10 cents] [Place a second dime next to the first dime.] If the value of one dime is 10 cents,CONCEPT DEVELOPMENT what is the value of two dimes? [20 cents] [Put a third dimeI. Showing tens on the board.] What is the value of three dimes? [30 cents] [Remove the dimes and put a penny on the board.] What isRemind the class that you can show two-digit numbers using the name of this coin? [a penny] What is the value of a penny?Dot Cards. Place a Dot Card-10 on the board. Ask: What number [1 cent] [Put a second penny next to the first penny.] What isdoes this show? [10] [Place a second Dot Card-10 on the board.] the value of two pennies? [2 cents] [Put a third penny on theWhat number does this show? [20] What if I would put seven Dot board.] What is the value of three pennies? [3 cents] [Leave theCards on the board? Would you need to count all of the dots to three pennies on the board, and put two dimes to the left ofknow what number it shows? [No] Why not? [because if there the pennies. Point to the dimes, and ask:] What is the value ofare seven filled-in Dot Cards, the number is 70] two dimes? [20 cents] [Point to the pennies, and ask:] What is the value of three pennies? [3 cents] So what is the value of two dimes and three pennies? [23 cents]II. Showing tens and ones Copyright © by SPOTS Educational Resources. All rights reserved.Place two Dot Card-10s and one Dot Card-7 on the board.Cover the Dot Card-7 with your hand or a piece of paper. Ask:What number does this show? [20] [Cover the two Dot Card-10s with your hand or a piece of paper.] What number does48