Mathematics_Year_2_Part_1

RUKUN NEGARA Bahawasanya Negara Kita Malaysia mendukung cita-cita hendak: Mencapai perpaduan yang lebih erat dalam kalangan seluruh masyarakatnya; Memelihara satu cara hidup demokrasi; Mencipta satu masyarakat yang adil di mana kemakmuran negara akan dapat dinikmati bersama secara adil dan saksama; Menjamin satu cara yang liberal terhadap tradisi-tradisi kebudayaannya yang kaya dan pelbagai corak; Membina satu masyarakat progresif yang akan menggunakan sains dan teknologi moden. MAKA KAMI, rakyat Malaysia, berikrar akan menumpukan seluruh tenaga dan usaha kami untuk mencapai cita-cita tersebut berdasarkan prinsip-prinsip yang berikut: KEPERCAYAAN KEPADA TUHAN KESETIAAN KEPADA RAJA DAN NEGARA KELUHURAN PERLEMBAGAAN KEDAULATAN UNDANG-UNDANG KESOPANAN DAN KESUSILAAN (Sumber: Jabatan Penerangan, Kementerian Komunikasi dan Multimedia Malaysia)

DUAL LANGUAGE PROGRAMME Year PART 1 Writers Editors Chan Yook Lean Asmahanim binti Ab Rahman Rosli bin Maun Mohd Faizal bin Rus Rzerli Translator Zaitun binti Othman Graphic Designers Illustrator Najmi bin Mat Sarit Wong Chi Ming Aini binti Abd. Hamid Awaludin bin Mohd Arof Dewan Bahasa dan Pustaka Kuala Lumpur 2018

Serial No.: 0157 ACKNOWLEDGEMENTS KK 513-221-0102021-49-1838-20102 The Ministry of Education would like to express ISBN 978-983-49-1838-5 its appreciation for the contributions made by First Printing 2017 the following: Second Printing 2018 © Ministry of Education Malaysia 2017 • The Panel of Evaluators, Textbook Division, All Rights Reserved. No part of this publication Ministry of Education Malaysia. may be reproduced or transmitted in any form or by any means, electronic or mechanical, including • Officers of the Textbook Division photocopying, recording, or any information and Curriculum Development Division, storage and retrieval system without permission Ministry of Education Malaysia. in writing from the Director General of Education, Ministry of Education Malaysia. Negotiation is • The Panel of Evaluators, subject to the calculation of royalty or honorarium. Dewan Bahasa dan Pustaka. Published for the Ministry of Education Malaysia by: • Officers of the English Language Teaching Centre (ELTC), Dewan Bahasa dan Pustaka, Teacher Education Division, Jalan Dewan Bahasa, Ministry of Education Malaysia. 50460 Kuala Lumpur. Telephone: 03-21479000 (8 hunting lines) • SK Taman Bukit Maluri, Kuala Lumpur. Facsimile: 03-21479643 Website: http://www.dbp.gov.my • SK Iskandar Shah, Perak. Design and Typeset: • All parties involved in the process of Dewan Bahasa dan Pustaka publishing this book. Text Typeface: Azim Text Size: 18 points Printed by: N.A.J. Press Resources (M) Sdn. Bhd., Lot 19, Jalan Lada Hitam 16/12, Seksyen 16, 40000 Shah Alam, Selangor Darul Ehsan.

CONTENTS 1 2 1 NUMBERS UP TO 1 000 6 RECOGNISE NUMBERS 8 WRITE NUMBERS 13 NUMBER VALUE 16 PLACE VALUE AND DIGIT VALUE 18 PARTITION NUMBERS 22 COMPARE NUMBERS 24 ARRANGE NUMBERS 29 COUNT NUMBERS 32 ESTIMATE NUMBERS 35 ROUND OFF NUMBERS 36 LET’S EXPLORE 40 NUMBER PATTERNS 44 SOLVE IT LET’S HAVE FUN iii

2 ADDITION, SUBTRACTION, MULTIPLICATION, 45 AND DIVISION ADD TWO NUMBERS 46 MORE ADDITION 51 ADD THREE NUMBERS 58 LET’S EXPLORE 61 SUBTRACTION 62 MORE SUBTRACTION 66 SUBTRACT SUCCESSIVELY 73 CREATE STORIES 76 SOLVE IT 78 MULTIPLICATION 8 1 BUILD UP TIMES TABLES 84 LET’S EXPLORE 88 BUILD UP 1, 0 AND 10 TIMES TABLES 91 LET’S EXPLORE 94 DIVISION 95 BUILD UP DIVISION TABLES 99 DIVISION INVOLVING 1, 10 AND 0 104 LET’S HAVE FUN 108 MORE DIVISION 109 CREATE STORIES 116 SOLVE IT 118 LET’S HAVE FUN 122 iv

PREFACE The Mathematics Year 2 textbook package is written based on the Standard-Based Primary School Curriculum Year 2 in line with the implementation of the revised curriculum starting from 2017. The writing of this textbook is tailored to meet the needs of the pupils to understand basic mathematical skills from the easiest level to the most abstract level. This textbook package is published to produce pupils who are able to apply mathematical knowledge and skills, effectively and responsibly in their daily lives. This textbook package consists of three components, namely Textbooks Part 1 and Part 2 and Activity Book. The topics contained in the textbooks are as follows: T•eNxtubmoobkePrasrt1: ••••T••FeMTLVrSDxieamoohatnclnabtuetgiaeopomtnyheose,skaMoPnfaadLsriDstq,e2uaci:idnmdals up to 1 000 • Addition, Subtraction, Multiplication, and Division All of these topics are also contained in the Activity Book. The textbooks focus on the goals of mathematics learning consisting of basic mathematical concepts and skills. The presentation of these books is tailored to incorporate related reasoning questions so that pupils can communicate as well as think critically and creatively. Each lesson is enhanced with formative exercises to be carried out either orally or in writing as well as additional activities proposed in the teacher’s notes. Furthermore, the recreational element in the lesson is infused via Let’s Explore and Let’s Have Fun to create an active and fun learning environment. Besides, moral values are instilled indirectly through the learning activities and pictures. The Activity Book provides reinforcement, remedial, and enrichment activities to strengthen and enhance pupils’ understanding on what they have learnt in the textbooks. Teachers are encouraged to prepare extra activities and exercises according to the pupils’ needs and abilities. The textbook package is hoped to provide meaningful and fun lessons as well as to increase pupils’ interest in mathematics. To use this textbook package, teachers can refer to the following explanation. v

SHAPES Shapes Song Learning topics 5 47 ÷ 7 = Remember the Stimulus page encourages Method 7 times table. Let us learn the 3-D shapes pupils to communicate 3-D shapes, 3-D shapes 6 6 x 7 = 42 Cuboid, cube, and pyramid 7 47 Cone and cylinder too – 42 5 remainder 47 ÷ 7 = 6 remainder 5 Twelve sides lengths are all the same 6 30 ÷ 8 = Six faces sizes all the same We can see these in dice Pupil-centred activities Method 1 Method 2 3 x 8 = 24 A cube, we call its name Questions of Higher Order Thinking skills (HOTs) 3 30 – 24 = 6. 8 30 remainder The remainder – 24 is 6. 30 ÷ 8 = 6 3 remainder 6 A cuboid has a different shape 30 ÷ 8 = 3 remainder 6 Six faces sizes not the same Has squares and also rectangles 00:9 Scan Hands-on There are 20 matchsticks. Has twelve sides too me activities A matchstick house such as needs 8 matchsticks. 9:00 projects and How many houses can games be made? Calculate the LET’S EXPLORE remainder of matchsticks. EACHENRO’TSES • Sing the song to the tune of The Mulberry Bush. While singing, pupils 7.1.1 Materials/Resources number cards 1 to 9 show 3-D shapes using real objects. 77 1 23456789 • Teacher is encouraged to add lyrics for other 3-D shapes. T T Method R BG 112 EACHENRO’TSES • Guide pupils to divide using concrete materials. 2.4.1 • Surf http://www.helpingwithmath.com/printables/worksheets/division/ T 1 Arrange the 1 47 L T div0301division08.htm Learning activities • Surf http://www.helpingwithmath.com/printables/worksheets/division/ via QR code number cards 258 div0301division09.htm according to the + 3 6 9 assigned colours. 7 7 4 Content Standard and 2 Change the arrangement of Learning Standard numbers within the R , B and G groups. What do you find? 3 Write five number sentences for the same total. 2 I arranged these I arranged the mooncakes in LET’S ANSWER Formative exercises to assess 2 rows. Each row mooncakes in understanding of learned skills has 4 mooncakes. 4 rows. Each Find the total. row has a 4 0 b 2 3 0 c 6 2 4 1 1 6 5 4 1 0 8 2 mooncakes. + 2 3 1 + 1 0 5 + 1 9 5 d 73 + 420 + 105 = e = 214 + 485 + 300 ET’S HAVE FUN f 148 + 217 + 364 = g = 453 + 299 + 147 Lucky Cards + 4 + 4 + 2 + 2 + 2 + 2 Materials/Resources 0 4 8 0 2 4 6 8 EACHENRO’TSES • Guide pupils to explore number addition through activities such as 2.1.2 20 fraction and decimal cards 2 times 4 makes 8. 4 times 2 makes 8. Let’s Explore to strengthen their understanding. 61 2 multiplied by 4 4 multiplied by 2 is equal to 8. is equal to 8. Front Back 2 × 4 = 8 4 × 2 = 8 Teacher’s guide to 1 0.8 8 teaching and learning 5 10 activities 2 × 4 is the same as 4 × 2 Participants 2×4=4×2 3 pupils per group Method Recreational 1 Place cards face down 2 The second player activities to foster on the table. opens one card. If any pupils’ Form a interest in The first player opens card matches, keep the number mathematics sentence. two cards. matching cards. × = 8 82 EACHENRO’TSES • Guide pupils to do simulation that involves columns and rows 2.3.1 to show the commutative law a x b = b x a. • Emphasise that the product will be the same even though the position of the multiplied numbers change. AB 56-57 • Surf https://www.ixl.com/math/grade-2/count-equal-groups Mascot stimulates critical and creative 3 Take turns. Repeat 4 The player who collects thinking to generate ideas step 2. Play until all the most cards wins. the cards are matched. 18 EACHENRO’TSES • Prepare sufficient cards for the activity. 3.1.1, 3.1.2 • Instil moral values such as honesty, integrity, patience, and tolerance. 3.1.5, 3.2.1 3.2.6, 3.3.1 Links to the pages in the activity book. T AB 101-102 Reinforcement activities Activity 2 SELF-ASSESSMENT to enhance skills learnt Remedial activities Answer the questions. Circle the answers horizontally or to assess understanding vertically in the number grid below. of basic skills Enrichment activities 1 Write the digit value of the underlined digits. 1 State the numbers. 3 What are the numMbeIrNs?D TEASER to test critical and a. One hundred and a. Cobm. plete the number puzzle. creative thinking a 361 b 247 c 8 9 5 twenty-four. vi b. Three hundred and five. a 1 3 b7 c c. Two hundred. 4 130 230 330 430 530 d 2 What are the numbers? a. What is the number ef g after 530? 1 9 1 3b. h d 920 100 100 100 100 5 What is the digit value 825 that is underlinedi? j k 100 30 8 e 807 f 6 Round off 375 to the Down nearest ten. 7 Round off 684 to the nearest huAndcrreods.s 1 2 4 9 2 7 4 a3. One hundred and b. Seven hundred and twenty. thirty-seven. c. Three hundred and four. 2 Complete these. 1 0 6 3 2 1 6 c0. What is the number? f. The number for this 9004 1 085 partition 700+5 is . a My place value b My digit value 1 2 3 4 5 6 7 d9. Complete the pattern. g. The number for is . is . is . 0 2 4 8 3 9 7 0 229 236 243 ? 257 My digit h. 6 hundreds + 9 tens + 0 ones value is 63098006 e. Round off 568 to the j. Round off 351 to the . My 4 8 1 2 3 4 0 7 nearest ten. nearest hundred. My place value place 5 0 5 0 1 7 0 h5. What is the k. 462 State the digit is . value is number? value of 6. My digit value . i. Count back in fives.VVeerryy ggoooodd Good TTrryy 29 aaggaaiinn is . 850 ? 840 835 1.4.1 Very Good Try k. 675, 683, 691, _____. good again What is the missing number? 8 TBP1 13-15 30 Very Good Try good again

NUMBERS UP TO 1000 PETRONAS TWIN TOWERS • Has 88 floors. • About 452 metres high. • The length of the bridge is 58 metres. • Has a hall with 865 seats. Each tower has eighty-eight floors. The height is about four hundred and fifty-two metres. T EACHENRO’TSES • Ask pupils to tell stories about the picture. 1.1.1 (i) 1 • Carry out an activity to get pupils to say the numbers involved in the given 1.1.1 (ii) facts individually or in groups.

RECOGNISE NUMBERS 15/1/2018 1 Monday Read or say your number. Three hundred and Eight hundred sixteen. and seven. Show the number nine hundred and thirty-five. 2 EACHENRO’TSES • In pairs, provide more reading activities of any number in words. 1.1.1 (i) T Get pupils to say the number using flash cards to strengthen pupils’ 1.1.1 (ii) understanding.

2 My number is Mine is three hundred and twenty-eight. four hundred and Mine is fifty-one. two hundred and ten. Mine is ten and one. Which number is said wrongly? Say it correctly. T EACHENRO’TSES • Get pupils to carry out activities of saying numbers in numerals or words 1.1.1 (i) 3 AB 1 1.1.1 (ii) in a quiz or question and answer session using calculators, computers, and others.

3 Letʼs match the number with its word. six heiugnhdtyre-fdivaend four htwuenndtryed and six fhifutyn-deriegdht seven hthurnedered and and seven hundred four hundred and and thirty nineteen four hundred and ninety-one seven hundred and thirteen 4 EACHENRO’TSES • Carry out number matching activity using words or vice versa in the 1.1.1 (iii) form of a game. Do it inside or outside the classroom. T • Carry out the activity of matching number cards with word cards. AB 2

603 630 Say these two numbers. What is the difference? LET’S ANSWER 1 Read and say the following numbers. a one hundred and b three hundred and twenty-three eighty c two hundred and seven d five hundred and nine e 819 f 477 g 670 h 908 2 Match. 320 two hundred and thirty 561 seven hundred and four 516 five hundred and sixty-one 230 three hundred and twenty 417 eight hundred and ninety-six 896 five hundred and sixteen 704 four hundred and seventeen EACHENRO’TSES • Train pupils to say the numbers on a number line. 1.1.1 (i) 5 • Provide more questions in question cards or worksheets. 1.1.1 (ii) 1.1.1(iii) T

WRITE NUMBERS 17/1/2018 1 Wednesday Write numbers in numerals. a one hundred and fifteen b one hundred and fifty 1 15 1 50 2 Letʼs write the numbers in words. 463 four hundred and sixty-three 510 five hundred and ten 709 seven hundred and nine 6 EACHENRO’TSES • Guide pupils to write numbers in numerals and words correctly in the 1.2.1 lined exercise book (three-lined book). T

3 I have written two hundred and thirteen. Which one is incorrect? Correct it. LET’S ANSWER 1 Write the numbers in numerals. a two hundred b three hundred and fifty c four hundred and sixteen d six hundred and eight 2 Write the numbers in words. a 543 b 780 c 817 d 902 EACHENRO’TSES • Emphasise to pupils to write numbers according to its value and not the 1.2.1 AB 3-4 individual digits. T 7 • Carry out an activity of writing numbers in numerals and words on a drawing paper using crayons and coloured pencils.

NUMBER VALUE One packet contains 10 kuih. 1 4 packets contain 40 kuih. 100 100 100 10 10 five hundred 10 10 and forty 540 100 100 2 What is the total number of marbles? 50 50 10 10 50 8 EACHENRO’TSES • Use real objects such as ice cream sticks and plastic straws for pupils 1.1.2 (i) to understand the number value of any given number. T

3 This shows a value of This shows a value of 526. 435. 526 435 4a 607 If 2 blocks of hundreds are taken out, what is the number now? b What is the number? EACHENRO’TSES • Emphasise the value represented by each base block through 1.1.2 (i) T simulation. 9 • Guide pupils to determine the object quantity for any given number value using counters, counting frames, abacus, paper squares, and others.

5 MathematIcs Corner Four hundred and twenty-six. 426 hundreds tens ones What is the number? 6 c ab hundreds tens ones 10 EACHENRO’TSES • Provide various numbers and ask pupils to show the numbers using 1.1.2 (i) T counters, abacus, and counting frames. Carry out activities in groups or individually. AB 5

7 Thursday 18/1/2018 Match each group of objects with its number. 125 214 362 345 8 Friday 19/1/2018 Arrange the number cards on the number line. 976 977 978 979 980 981 The numbers are getting larger. EACHENRO’TSES • Carry out activities of matching groups of objects such as counters, 1.1.2 (ii) counting frames, and abacus with the number value as a competition T using flash cards. 11

Do the base blocks show the same numbers? Why? LET’S ANSWER 1 Show the following numbers using base blocks and abacus. a 160 b 517 c 739 d 908 2 What is the number? ab 100 100 100 20 10 10 10 10 cd f ef hundreds tens ones 12 EACHENRO’TSES • Emphasise that 10 tens is the same as 100 and 10 ones is the same 1.1.2 (i) T as 10. 1.1.2 (ii) • Surf https://www.slideshare.net/mazlan81/modul-pp-matematik- AB 6 nombor-dan-operasi-thn-2

PLACE VALUE AND DIGIT VALUE 1 1, 4 and 2 are the numbers found in one hundred and forty-two. What is the place value of 1, 4 and 2? 142 1 hundreds 4 tens 2 ones The place value of 1 is hundreds. hundreds tens ones The place value of 4 is tens. 1 4 2 The place value of 2 is ones. 2 State the place value of 3, 6 and 0 in 360 . The place value of 3 is hundreds, 6 is tens, and 0 is ones. hundreds tens ones hundreds tens ones 3 6 0 EACHENRO’TSES • Guide pupils to understand the place value using counters, base blocks, 1.4.1 counting frames, and place value charts. T 13 • Emphasise that place value is the position of digits in a number.

3 There are digits The The digit value digit value 5, 7 and 9 in 579. of 5 is 500. of 7 is 70. 500 70 9 579 The digit value of 9 is 9. 4 What is the digit value of 8, 3 and 1 in 831? 8 3 1 The digit value of 1 is 1. The digit value of 3 is 30. 831 is 800 + 30 + 1. The digit value of 8 is 800. 800 831 30 1 14 EACHENRO’TSES • Carry out a question and answer activity about digit value by providing 1.4.1 T various numbers to test pupilsʼ understanding. • Explain that digit value is a value of a number according to its position in that particular number.

5 907 Say the place value and digit value of 9, 0 and 7. Digit 9 0 7 Place value hundreds tens ones Digit value 900 07 Digit 9 is in hundreds place and the value is 900. Digit 0 is in tens place and the value is 0. Digit 7 is in place and the value is . 7 Form a three digit number: 08 a the largest b the smallest from the number cards. State the place value and digit value of each number. LET’S ANSWER Write the place value and digit value for the underlined digits. Number Place value Digit value 450 612 793 802 15EACHENRO’TSES • Emphasise that the value for a number is determined based on its digit 1.4.1 value and place value. T • Provide more questions in question cards or worksheets. AB 7-9

PARTITION NUMBERS 1 Partition 182. 1 100 hundreds 8 tens 80 2 ones 182 2 Partition based 182 1 hundreds + 8 tens + 2 ones on place value 182 100 + 80 + 2 Partition based on digit value 2 hundreds + tens + Try to ++ complete this. 16 EACHENRO’TSES • Guide pupils to partition the numbers according to its place value or 1.4.2 digit value. T • Carry out a game using number cards and partition cards for pupilsʼ understanding.

3 Partition 640. 6 600 hundreds 40 Digit 640 Place 4 tens 0 Value Value 0 ones 640 600 + 40 + 0 640 6 hundreds + 4 tens + 0 ones 703 3 ones + 7 hundreds + 0 tens Can you partition 703 3 + 700 703 as shown? Discuss. LET’S ANSWER Partition these numbers. +7 a 297 2 hundreds + 9 b 605 + 0 tens + c 814 800 + + d 930 + 30 + T EACHENRO’TSES • Emphasise the method of writing the place value and digit value 1.4.2 AB 10-11 correctly. 17 • The digit value 0 is not necessarily written when partitioning the number to digit value.

COMPARE NUMBERS 1 It is 256 altogether. It is 356 altogether. I have 100 more. Determine which number is larger, 256 or 356. 200 300 Firstly, look at the 300 is 100 more hundreds value. than 200. 300 is larger than 200 . 356 is larger than 256. 18 EACHENRO’TSES • Carry out an activity of comparing two numbers using counters 1.1.2 (iii) or other suitable objects. T • Emphasise to pupils to compare the numbers starting from the largest place value.

2 418 415 Which number is smaller? Hundreds hundreds tens ones value is the same. Tens The ones value is also value is not the same. the same. 4 18 4 15 5 is smaller than 8. 415 is smaller than 418. Which number is smaller? Explain. hundreds tens ones hundreds tens ones 623 643 EACHENRO’TSES • Emphasise that the larger number represents a larger value. 1.1.2 (iii) AB 12 • Provide various numbers in an activity of comparing numbers T 19 to strengthen pupilsʼ understanding.

3 Which number is more, 856 846 856 or 846? hundreds tens ones The hundreds is the same. 8 5 6 Compare the tens. 8 4 6 5 tens is more than 4 tens. 856 is more than 846. 4 Compare 457 with 97. hundreds tens ones 97 is larger than 457. 4 5 7 9 7 Is it correct? Discuss. Form two numbers of three digits. 1 3 5 The largest digit is placed in tens. Compare. 20 EACHENRO’TSES • Emphasise that a number with more digits has a larger value. 1.1.2 (iii) T • Apply the words of ‟larger than”, ‟smaller than”, ‟more than”, and ‟less than” when comparing number values.

5 917 920 Which number is less, 917 or 920? 916 917 918 919 920 917 is placed before 920. The more to the 917 is less than 920. right, the greater the number. Where are 703 and 718 located in the following number line? Compare. 700 705 710 715 720 LET’S ANSWER 1 What is the number? Which number is larger? ab hundreds tens ones hundreds tens ones 2 Determine the smaller number. a 550 505 b 978 996 EACHENRO’TSES • Provide more questions in question cards or worksheets to strengthen 1.1.2 (iii) AB 13 pupilsʼ understanding. 21 T

ARRANGE NUMBERS 1 RECYCLIng PROGRAMME 2 Jauhari 2 Bestari 2 Potensi 2 Cerdik 206 170 160 215 Which class collected the most cans? 1.1.2 (iv) Arrange the numbers from the smallest to the largest. 160 , 170 , 206 , 215 The number is getting larger. This is an ascending order. We can also arrange the numbers in a descending order. The highest value is 215. 215 , 206 , 170 , 160 The number is getting smaller. This is a descending order. Year 2 Cerdik collected the most cans. 22 EACHENRO’TSES • Carry out games and simulation using number arrangement. T • Surf http://www.kidsfront.com/math/l.ascendorderl2.html • Surf http://www.kidsfront.com/math/l.descendorderl2.html

2 120 , 122 , 124 , 126 Ascending order Descending 126 , 124 , 122 , 120 order 3 Discuss the number arrangements above. LET’S ANSWER 1 Arrange the numbers in ascending order. 809 920 909 816 960 2 What are the numbers? Arrange the numbers in descending order. EACHENRO’TSES • Carry out an activity of arranging number cards in ascending and 1.1.2 (iv) AB 14-15 descending order outside the classroom. T 23 • Emphasise that the ascending and descending orders follow a pattern.

COUNT NUMBERS We count on in hundreds from 1a 200. It is 600 200, 300, altogether. 400, 500, 600. 200 300 400 500 600 b Count. What is the total? 400 500 600 ? ? 2 I count on in tens. 600, 610, 620, 630, 640, 650. 600 610 620 630 640 650 24 EACHENRO’TSES • Carry out an activity of saying and counting numbers using objects, 1.3.1 picture cards, and abacus. 1.3.2 T

3 a Count on in fives. 100 105 110 115 ? b Count on in sixes. ? 418 ? 400 406 c Count on in eights. 700 708 716 724 732 ? ? 4 155 The numbers are reduced in ones. We count back in ones. 157 156 154 153 152 151 T EACHENRO’TSES • Carry out an activity of counting and completing a number series 1.3.1 using picture cards, number cards, and number lines. Provide various 1.3.2 25 number sequences such as ascending or descending in ones, twos, threes, fours, sevens, and nines.

5 518 418 318 218 Count back in hundreds. 6 a Count back in twos. 160 158 168 166 164 ? b Count back in sixes. 290 ? 302 308 314 320 326 c Count back in sevens. ? 686 693 700 707 714 721 26 EACHENRO’TSES • Carry out a game outside the classroom. Each pupil has five 1.3.1 T number cards. Ask them to arrange the numbers in ascending and 1.3.2 descending orders. Provide a few sets of number cards to perform this activity.

7 845 211 401 411 431 441 837 205 829 202 821 199 813 196 200 400 100 404 408 416 420 Say the missing numbers. T EACHENRO’TSES • Carry out an activity of counting and completing the numbers in the 1.3.1 AB 16-18 picture. Conduct a question and answer session with pupils about number arrangements, in ascending or descending order. 1.3.2 27

LET’S ANSWER 1 Count the numbers. Say whether the following number sets are in ascending or descending order. a 222 224 226 228 230 232 b 438 428 418 408 398 388 c 635 640 645 650 655 660 d 970 870 770 670 570 470 2 Complete these. 927 928 929 920 LET’S ANSWER 909 911 913 917 906 906 900 892 902 912 897 812 712 28 EACHENRO’TSES • Provide more questions in question cards or worksheets involving 1.3.1 T counting numbers in ones until tens and hundreds and also 1.3.2 completing number sequences.

ESTIMATE NUMBERS 1 There is about half a container of keropok lekor left. 200 Estimate the keropok lekor in the container. I estimate it is I estimate it is less than 200. more than 100. 200 ? T EACHENRO’TSES • Guide pupils to do estimation according to the given reference set. 1.5.1 Train pupils to use ‟about”, ‟less than”, and ‟more than” when comparing. 29 • ‟Approximately” can also be used instead of ‟about”.

2 Estimate the numbers in the pictures. a 50 about 100 b The 100 number is c less than 100. ? 50 ? 30 EACHENRO’TSES • Guide pupils to make a reasonable estimation on the number 1.5.1 of objects. T • Emphasise that estimation is a process of determining the nearest value, not random guesses.

3 The green money box has The yellow money box about 400 coins of 50 sen. has about 200 coins of 50 sen. Discuss the estimated number of 50 sen coins in the red money box. rr LET’S ANSWER Estimate the number. Use the terms ‟about”, ‟less than” or “ more than”. ab 10 ? 100 ? 31EACHENRO’TSES • Provide more activities on estimation using objects or picture cards 1.5.1 T to strengthen pupilsʼ understanding. • Surf https://www.ixl.com/math/grade-2/estimate-to-the-nearest-ten AB 19-20

ROUND OFF NUMBERS 1 230 231 232 233 234 235 236 237 238 239 240 a Round off 232 to the nearest ten. 230 232 235 240 232 is nearer to 230. 232 when rounded off to the nearest ten becomes 230. b Round off 237 to the nearest ten. 230 235 237 240 237 is nearer to 240. . 237 when rounded off to the nearest ten becomes What will happen if the bicycle is at 235? 32 EACHENRO’TSES • Emphasise that pupils need to look at the tens and ones digits to round 1.6.1 off three digit numbers to the nearest ten. T • Carry out simulation of rounding off numbers to the nearest ten using base blocks.

2 Round off 465 to the nearest ten. Method 1 460 465 470 465 is in the middle of 460 and 470. Method 2 465 470 If the ones digits are 5, 6, 7, 8 or 9, round it off to the nearest larger ten. 465 when rounded off to the nearest ten becomes 470. 3 Round off 734 to the nearest hundred. 734 700 730 750 800 734 is nearer to 700. 734 when rounded off to the nearest hundred becomes 700. 33EACHENRO’TSES • Emphasise that if the number is in the middle of two tens successively, 1.6.1 round off the number to the nearest larger ten. T • Surf http://www.k5learning.com/worksheets/math/grade-2-round- 3-digit-numbers-nearest-10-a.pdf and http://www.k5learning.com/ AB 21 worksheets/math/grade-2-round-3-digit-numbers-nearest-100-a.pdf

4 Round off 859 to the nearest hundred. Method 1 859 800 850 860 900 Method 2 859 is nearer to 900. 859 900 If the tens digit is 5, 6, 7, 8 or 9, round it off to the nearest larger hundred. 859 when rounded off to the nearest hundred becomes 900. 5 Look at the number line. Which numbers become 360 when rounded off to the nearest ten? 350 351 352 353 354 355 356 357 358 359 360 Numbers that become 360 when rounded off to the nearest ten are 355, 356, 357, 358 and 359. 34 EACHENRO’TSES • Emphasise that pupils need to observe the hundreds and tens digits 1.6.1 to round off three digit numbers to the nearest hundred. T • Provide exercises using various numbers to strengthen pupilsʼ understanding.

6 550 560 570 580 590 600 610 620 630 640 650 550 to 599 and 601 to 649 when rounded off to the nearest hundred become 600. 257 can become LET’S ANSWER 260 or 300 when it is rounded off. Explain. Round off the numbers to the nearest hundred. a 421 b 586 c 655 d 907 LET’S EXPLORE Materials/ coins, a container filled Resources with numbers, paper, pen Participants 2 players and a referee Method 1 Pick a number. 2 Toss a coin. If it is heads, round off Heads Tails the number to the nearest ten. If it is tails, round off the number to the nearest hundred. 3 The referee will record 2 points for every correct answer. 4 The player with the highest points wins. T EACHENRO’TSES • Emphasise that when rounding off numbers to the nearest ten, the 1.6.1 AB 22-23 rounded off value is in multiples of ten. When rounding off numbers to 35 the nearest hundred, the rounded off value is in multiples of hundred. • Relate the importance of rounding off in daily life such as rounding off the price of goods and services.

NUMBER PATTERNS I count on 1 in ones. 99 100 101 102 103 What is the number pattern above? The numbers 99 100 101 102 103 are arranged increasingly in ones. The number pattern is increasing in ones. 2 118 120 122 124 126 The number pattern is increasing in twos. 3 What is this number pattern? 316 516 216 416 36 EACHENRO’TSES • Carry out a number pattern simulation by counting objects in the class 1.7.1 in ones to tens and hundreds. T • Guide pupils to state the number patterns.

4 The numbers 242 241 240 239 238 are arranged decreasingly in ones. The number pattern is decreasing in ones. 5 430 438 436 434 432 . The number pattern is decreasing in 6 635 535 435 335 235 The number pattern is . 7 Talk about the number patterns. a 520 516 512 508 504 b 800 795 790 785 780 c 928 938 948 958 968 T EACHENRO’TSES • Guide pupils to recognise decreasing number patterns based on 1.7.1 several number series. Relate them to counting back in ones to tens and hundreds. 37

8a The number pattern is increasing in tens. 170 180 190 ? ? b This number pattern is increasing in threes. 216 219 222 ? ? c This is a descending order. So, its number pattern is decreasing in hundreds. 589 489 389 289 189 ? What is the next number in the number pattern above? Arrange these numbers to form a pattern. 655 , 650 , 675 , 660 , 670 , 665 , 645 38 EACHENRO’TSES • Emphasise that number patterns are related to number arrangements 1.7.2 in ascending and descending orders in ones to tens and hundreds. T • Carry out an activity of completing number patterns based on the AB 24-26 given number lines and number strips.

LET’S ANSWER 1 Complete the following number patterns. a 100 103 106 109 115 b 465 365 265 165 65 c 807 783 789 795 2 Look at the number grid. The number pattern in the blue boxes is increasing in threes. State five numbers for the patterns below. 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 a Increasing number patterns: i in twos. ii in fives. iii in eights. iii in sevens. b Decreasing number patterns: i in fours. ii in sixes. EACHENRO’TSES • Provide more questions in worksheets and question cards. 1.7.1 39 • Surf www.fuelthebrain.com/games/line-dry/ 1.7.2 T

SOLVE IT 0 14 7 Izah has three number cards as above. She puts 7 in hundreds, 4 in ones, and another card in tens. What is the number? Write the answer in words. Method hundreds tens ones Arrange the 7 0 4 numbers according to the place value. The number is seven hundred and four. Round off 704 to the nearest hundred. Discuss. 40 EACHENRO’TSES • Guide pupils to understand the question by jotting down important 1.8.1 information. T • Provide more questions in worksheets and question cards to strengthen pupilsʼ understanding.

2 The picture shows the number of books read by the three pupils. Who is the winner? Bee Yee Lim Wong 248 268 246 Method 1 Determine the largest number. I use blocks. 248 268 246 The largest number is 268 Method 2 Arrange the numbers in ascending order. 246 , 248 , 268 268 is the The largest number is 268 number of books read The winner is Lim. by Lim. T EACHENRO’TSES • Guide pupils to underline the important information in the question 1.8.1 to solve them. 41 • Guide pupils to check their answers through simulation.

3 The picture shows the marks obtained by 2 pupils in a quiz. Balaʼs mark is not shown. Gana Bala Rani Bala scored 10 marks less than Gana and 10 marks more than Rani. What is Balaʼs mark? Method Draw a number line. 10 more + 10 438 448 458 – 10 10 less Bala’s mark is 448. 42 EACHENRO’TSES • Guide pupils to solve the problem using a number line. 1.8.1 T AB 27-28