Class-4

Class-4 Day-8 Activity Here, look and study the given figure. AB C D AB = 4cm AB + BC = 7cm BC = 3cm AC = 7cm BC + CD = 5cm BD = 5cm Exercise Find the following length by using a ruler . P Q RS a) PQ + QR PR = b) QR + DS = QS = c) PR +QS = d) PQ + QR +DS = Day-9 Activity Read and observe the table from pg. 6 of your maths book to learn how to draw a line segment of given length. Exercise Construct the line segment of given lengths. a) 5cm b) 3cm c) 4.3 cm Identify the following: a) b) c) d) e) f) --51--

Mathematics Day-10 Activity Read pg.- 8 from your maths book and learn how to count number of faces, vertices and edges of solid shapes. Exercise Write down the number of faces, edges and vertices of the following figured: a) b) c) Day-11 Activity Two rays or line segments with a common point form an angle. The common point of the two rays (arms) is called vertex of the angle. Two rays or line segments are called arms of the angle. In figure, ray OA and ray OB are arms and the point O is the vertex of the angle. A arm angle vertex O B Exercise arm Name the arms and vertex from the given angles. a) A b) c) P NO BC M QR Day-12 Activity Capital letters of the English alphabet are used to name an angle. The letter denoting the vertex of angle is always written in the middle. X Y Z This is ∡XYZ or ∡ZYX. --52--

Exercise c) X Class-4 Name the following angles. N Y Z D AC f) C a) b) B BC M d) S e) Y PT W X Activity Day-13 Square corner Smaller than a right angle Greater than right angle. Exercise Identify each angle as right, acute or obtuse. a) b) c) d) e) f) Day-14 Activity  Observe pg. -12 as well as activity and Activity 13 and learn how to draw the different angles. Exercise a) Draw different five angles which are acute. b) Draw any two right angles. c) Draw any five obtuse angles. --53--

Mathematics Day-15 Activity Observe, look and study pg. -13 from your maths book and learn how to measure an angle. Exercise Name the angles and the size of the angle. P a) A b) B CQ R c) d) V S TU WX Day-16 Activity- Observe, Look and study pg. -14 and learn how to draw an angle of given measures. Exercise b) 45o c) 155o a) 35o Day-17 Activity Look, study and learn pg. 13 and 14, to find out how to measure an angle. Exercise d) Measure the following angles and write. J a) b) c) A DD B C E FE F K L --54--

Class-4 Day-18 Activity From pg. 15 look study and learn about kinds of angles. Exercise Write A for acute, O for obtuse, R for right and S for straight angles respectively. c) 180o d) 110o a) 60o b) 20o h)130o i) 75o e) 90o f) 161o g) 43o j) 175o Day-19 Activity Smaller than a right angle Square corner Acute angle Right angle Straight angle Greater than right angle. c) Obtuse angle Exercise Classify the following angles. a) b) d) e) f) --55--

Mathematics Day-20 Concept of number Activity Look and study pg. - 22 and learn how to write number name of the given number in national system. eg. 491313 = Four lakhs Ninety one thousands three hundreds and thirteen. Exercise Write the number name for each of the following numbers. a) 1233456 b) 203467 c) 552583 d) 775709 e) 965370 Day-21 Activity - Smallest one digit number is 1 and greatest one digit number is 9. - Smallest two digit number is 10 and greatest is 99. - Smallest three digit number is 100 and greatest is 999. - Observe pg. - 22 for more information. Exercise Write the smallest and greatest number of following. S. N. Digits Smallest Greatest (largest) a. 1 digit b. 2 digits c. 3 digits d. 4 digits e. 5 digits f. 6 digits g. 7 digits h. 8 digits Day-22 Activity - By using the digits given below, make the largest number possible. 7, 5, 9, 1, 3 Largest number = 975113 - Large digits should be put first while making largest number using given digits. ( larger to smaller) - Zero should kept at last. --56--

Exercise Class-4 c) 9, 0, 4, 3, 6, 8 Make the largest number using following digits. a) 4, 2, 6, 8, 9 b) 8, 7, 6, 2, 5, 8 d) 1, 5, 9, 4, 8, 6 e) 2, 4, 8, 6, 4, 1 Day-23 Activity - By using the digits given below make the smallest number possible. 4, 9, 7, 0, 6 Smallest number = 40679 - Small digits should be kept first while making smallest number. (Small to large) - can not be kept at first. Exercise Make the smallest number using following digits. a) 4 2 9 7 6 0 b) 8 9 7 5 4 1 c) 2 7 9 5 3 0 d) 8 6 8 7 9 1 e) 3 0 0 4 0 6 Day-24 Activity Look and study the given abacus. L T-Th Th H T O Numeral: 5 0 4 2 0 0 Number Name : Five lakhs four thousands and two hundreds. Exercise Study the given abacus and write numeral as well as number name as given in example. a) L LTTTT L T- T H T O --57--

Mathematics Day-25 Activity Observe activity of day - 24 and pg. -23, Q.N. : 9a from your maths book. Exercise e) 798062 Prepare the abacus for the following numerals . a) 43016 b) 486291 c) 910494 d) 616104 Day-26 Activity Look and study pg. 24 and learn how to make the national place value chart. e.g. 2, 47, 531 Lakh Ten Thousands Thousand Hundred Ten One 24 7 5 31 = Two lakhs forty seven thousand five hundred and thirty - one. Exercise Draw the place value chart for the given numbers and write the number names. a) 886706 b) 571936 c) 43775 d) 555283 Day-27 Activity - When we multiply face value with place, the result is place value. eg. 8 9 5 4 2 Here, 9 is in thousands place, so, 9×1000 = 9000 ∴ 9000 is the place value of encircled digit. Exercise Write the place value of encircled digit in each of the following. a) 6 6 7 6 3 1 b) 2 6 3 2 4 c) 9 9 8 7 8 6 d) 8 05 0 3 0 f) 7 6 5 4 2 2 --58--

Class-4 Day-28 Activity  If a number is made with 8 digits, this number is up to one crore.  Study Pg. - 26 and learn about the number up to one crore. 26494504 = Two crores sixty four lakhs ninety four thousands five hundreds and four. Exercise Write the following population of Nepal in words. a) 23151423 b) 28152794 c) 18491097 d)15022834 e) 11555983 Day-29 Activity Write the numeral for the given number name. Seven crores six lakhs, thirty one thousands, six hundreds and eighty six. = 7,06,31,689 Exercise Write numeral for each of the following: a) Sixty - four lakhs, twenty thousands, four hundreds and seven. b) Eight crores, eighty - eight lakhs, eighty - eight thousands four hundred and forty - four. c) Nine crores, seventy thousands and eighty - nine. Day-30 Activity Read the following international place value chart and learn the differences between national place value chart and international place value chart from page - 27. E.g.47625043 Millions Thousands Ones H T O H T O HT O 4 7 6 2 5 04 3 Forty seven millions six hundred twenty-five thousands and forty-three. Exercise Write the given number by making international place value chart and write the number name. a) 6781436 b)7894568 c)8004534 d) 61664122 --59--

Mathematics Day-31 Activity  Learn the differences between national and international place - value charts from pg. - 27. Exercise Write the following numbers in national place value chart and number name as well as international place value chart and number name. a) 6469576 b) 4254046 Day-32 Activity  Learn the comparison between national and international place value chart from pg. - 27. Exercise Fill in the blanks. a) 100 thousands = 1 lakhs b) 10 lakhs = _____ millions c) 40 millions = ______ crore d) 700 thousands = _______ lakhs e) 1 million = _______ lakhs f) 10 millions = ______ crore g) 100 millions = ______ crores Day-33 Activity 20 30 40 50 60 27 Here, 27 lies between 20 and 30, but it is nearer to 30 than to 20. So,27 is rounded off to 30 when we round off to nearest 10. Exercise Round off the following numbers to the nearest ten. a) 76 _______ b) 83 _______ c) 177 ________ d) 1248 _______ e) 3264 _______ f) 8091 ________ g) 9663 _______ h) 2006 _______ --60--

Class-4 Day-34 Activity 100 200 300 400 500 600 340 Here, 340 lies between 300 and 400 but it is nearer to 300 than to 400. So, 340 is rounded off to 300 when we round off to nearest 100.  Learn more from pg. - 29 to round off to nearest 100. Exercise Round off the following numbers to the nearest 100. a) 783 ______ b) 108 ______ c) 480 ______ d) 207 ______ e) 10441 _____ f) 28117 _____ g) 34188 _____ h) 893 _____ Day-35 Activity 1000 2000 3000 4000 5000 6000 4600 Here, 4600 lies between 4000 and 5000, but it is nearer to 5000 than to 4000. So, 4600 is rounded off to 5000 when we round off to nearest 1000. Exercise Round off the following numbers to nearest 1000. a) 6450 ______ b) 9780 _______ c) 1148 ______ d) 11497 ______ e) 44682 ______ f) 28425 _____ Day-36 Activity  Look study and learn pg. - 31 to know about prime numbers.  The numbers which are exactly divisible by 1 or by the number itself but not by other numbers are known as the prime numbers. --61--

Mathematics Exercise Write all the prime numbers between: a) 1 and 15 b) 25 and 45 c) 40 and 60 d) 35 and 55 Day-37 Activity  Look study and learn pg. - 32 (composite numbers)  Composite numbers are divisible by other numbers more than 1 and number itself. Exercise d) 65 and 85 Write all the composite numbers between. a) 20 and 30 b) 26 and 40 c) 45 and 75 Day-38 Activity  1 is not considered as prime number.  2 is only one even prime number.  Look study and learn pg. - 32 for more information. Exercise Circle the prime numbers from given numbers. 1, 2, 5, 8, 11, 17, 19, 21, 23, 27, 29, 49, 53, 57, 68, 69, 73, 77, 81, 84, 89, 93 Day-39 Activity  9 is a composite number because it is exactly divisible by 3.  All even numbers are also composite numbers.  Some odd numbers are composite and some of the odd numbers are prime.  Look study and learn pg. - 32 for more information. Exercise  Circle the composite numbers from given numbers. 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 17, 18, 19, 23, 27, 31, 37, 39, 43, 45, 48, 49, 51, 53, 67, 77, 97, 103, 117, 121 --62--

Class-4 Day-40 Activity  Factors of a number are all the whole numbers that divide into if exactly. Factors of 8 are 1, 2, 4 and 8.  1 is factor of every number.  Any number is factor of itself. Exercise List out the factors of given numbers. a) 15 b) 16 c) 27 d) 36 e) 63 f) 90 Day-41 Activity  Observe Pg. - 34 example, and learn about prime factors. Exercise Complete the following factor trees. 54 a) 2 9 3 24 c) 75 b) 25 2 12 5 26 2 --63--

Mathematics Day-42 Activity Observe Pg. - 34, example, solution B and lean about prime factorization. Exercise Find the prime factorization of the given numbers. a) 42 b) 50 c) 60 d) 96 Activity Day-43 Find the HCF of 20 and 30 30 15 Solution: 5 2 20 2 2 10 3 5 Here, 20 = 2 × 2 × 5 30 = 2 × 3 × 5 HCF = Product of common factors = 2 x 5 = 10 # Exercise b) 12 and 18 Find the HCF of given numbers. d) 32 and 48 a) 8 and 12 c) 12 and 30 Day-44 Activity Let's take two number 4 and 6, the multiples of 4 and 6 are, 4 = 4, 8, 12, 16, 20, 24, 28, 32 __________ 6 = 6, 12, 18, 24, 30, 36 ________ LCM = Lowest common multiple = 12 # Exercise Find the LCM of following numbers. a) 2 and 3 b) 6 and 8 c) 5 and 10 d) 6 and 10 e) 8 and 10 f) 6 and 9 --64--

Day-45 Class-4 1000 - M Activity Hindu Arabic and Roman numbers. 1 = I, 5 = V, 10 - X, 50 - L, 100 - C, 500 - D, VI = 5 + 1 = 6 III = 1 + 1 + 1 = 3 IV = 5 - 1 = 4 XI = 10 + 1 = 11 IX = 10 - 1 = 9 XV = 10 + 5 = 15 XX = 10 + 10 = 20 Rules of Roman numbers: 1) The symbols I, X, C and M can be repeated three times. 2) If the smaller symbol is right to the greater, if is added. But V, L and D are never added. 3) If the smaller symbol is left to the greater, it is subtracted. But V, L and D are never subtracted. 4) If the smaller symbol is between greater, if is subtracted from the right one. Exercise Write the Hindu Arabic numerals for the following. a) XXIV b) XLI c) XCIV d) CDXX e) CMXIX f) MMDCXL Activity Day-46 Addition: 111 Exercise 1 0 6 82 2 1 3 15 +3 2 1 6 8 64165 Add the following: a) 237 b) 1 9 217 +8 4 6 +3 3 121 --65--

Mathematics 1 7 53 7 6 1 88 d) 2 1 64 c) 2 1 3 3 4 4 18 + 8 68 +2 9 0 3 Activity Day-47 Subtract: 3 13 14 5 12 Exercise 4 4 4 6 62 − 8 6056 3 5 8 6 06 Subtract the following: a) 6 5 7 b) 7 1 38 c) 4 6 48 −5 8 2 −2 4 53 −3 7 25 d) 6 7 33 e) 9 7 422 −3 9 04 −3 1 754 Day-48 Activity Look and study the given example. 7 6 459 Minuend −5 4 2 5 6 Subtrahend 2 2 2 03 Difference Exercise a) Find the difference if minuend is 35678 and the subtrahend is 2740. b) Find the difference is subtrahend is 825989 and the minuend is 956843. Day-49 Activity What number is 4669 less than 50000?  Here, Big number = 50,000 Small number = 4669 --66--

Class-4 9 9 9 10 So, 5 0 000 − 4 669 4 5 3 31 45331 is 4669 less than 50000 # Exercise a) Which number is 2345 less than 8989. b) Which number is 200 less than 3672? c) Which number is 20 less than smallest five digit number? Day-50 Activity What number should be added to 28088 to get 461000? 10 9 9 10  Here, 4 6 1000 Big number - small number − 2 8088 4 3 2 9 12 432912 should be added to 28088 to get 461000. Exercise a) What must be added to 3532 to get 65974? b) What must be added to 42435 to get the largest 6 digits number. c) Find the sum of 8998 and 76893, then subtract 5913 from the result. Day-51 Activity  Look study Pg. 43 from your book and learn about word problems of subtraction. Exercise a) In March, Deepa had Rs. 85675 in her bank account. In April, she had Rs. 62480 in the bank. What was the decreased amount in one month? b) A car is worth Rs. 969000 and a van is worth Rs. 747000. Which is more expensive and by how much? c) The population of Bharatpur is 147777 and population of Ratnanagar is 46607. Find the difference of the population. --67--

Mathematics Day-52 Activity Look and study Pg. - 43 from your book and learn how to solve word problems. Exercise a) In a examination of B.S. 2073,4,56,719 students appeared in the examination and 2,54,962 passed in the examination. How many students were failed in the examination? b) In a examination of B.S. 2068,495998 candidates has appeared in the exam. Among them 208235 were passed in the result. How many students were failed? Day-53 Activity Set is a collection of well defined objects. This is a collection of flower. It is a set of flower. ___________ Exercise ___________ Write the set of the following as above. ___________ ___________ a) ___________ ___________ b) ___________ c) ___________ d) a, e, i, o, u ___________ e) 1, 2, 3, 4, 5 ___________ --68--

Class-4 Day-54 Activity  A set is a collection of distinct objects. In other words set is a collection of well defined objects. Well defined means can state clearly.  We can make a set of birds but we cannot make a set of beautiful birds.  We can make a set of students of class - 4, but we cannot make a set of tall students of class - 4 because this is not well defined. Exercise Write 'Yes' if following statements form a set otherwise write 'No'. a) The set of all rivers in Nepal. b) The set of seven days in a week. c) The set of clearer boys in your class. d) The set of English alphabet. e) The set of beautiful flower. f) The set of colours of a rainbow. Day-55 Activity Cap is not related to this set. Now, this is a set of flowers. Exercise Pick out the odd one from the following collection and write down a clear set for the remaining objects. a) b) c) d) 1, 2, 3, 4, 5 a, e) --69--

Mathematics Day-56 Activity Read look study and learn from pg. 196. Exercise Name these sets and members of the sets. a) b) c) d) e) Day-56 Activity  A set should be well defined. For example: A bird cannot put in the set of insect and a mosquito cannot put in the set of birds. Exercise Write 'True' or 'False' for the following. a) A bird is a member of the set of insects. --70--

Class-4 b) A triangle is a member of the set of geometrical shapes. c) Sunday is a member of the set of days in a week. d) 2 is a member of the set of even numbers. e) The moon is a member of the solar system. f) A banana is a member of the set of flower. Day-57 Activity Here, A = {rose, lotus, lily, marigold}  Each number is separated by comma (,) and enclosed by curly brackets {}. We use capital letters A,B,C,D .......... to denote a set. Exercise List the elements of the following sets. a) a, e, i, o, u ______________ b) 1, 2, 3, 4 ____________ c) d) e) Day-58 Activity If a member is in the set this member is belongs to the set. The symbol of belongs to is ∈. If a object is not in the set, this object does not belong to the set. The symbol of does not belong to is∉. If A = {1, 2, 3, 4, 5} 1 ∈ A (1 is belongs to the set A) 4 ∈ A (4 is belongs to the set A) 6 ∉ A (6 does not belong to the set A) --71--

Mathematics Exercise Rewrite the following using set notation. a) x belongs to the set X. b) 8 is an element of the natural number N. c) b does not belong to the set V. d) O is an element of the set of whole number W. e) e does not belong to the set A. Activity Day-59 If A = {1, 2, 3, 4, 5} 2∈A 4∈A 1 ∈A 5 ∈A 6∉A 8 ∉A 3∈A 7∉A Exercise If A = {a, b, c, d} and B = {a, e, i, o, u} Write the following as true or false. a) a ∈ A b) b∈ B c) c ∈ A f) u∈ A d) a ∈ B e) e ∈ B Day-60 Activity List the elements of the following sets. i) The set of first five natural numbers = { 1, 2, 3, 4, 5} Exercise List the elements of the following sets. a) The set of first five months of a year. b) The set of seven days of a week. c) The set of capital city of Nepal. d) The set of three odd numbers. --72--

Class-4 Self-Evaluation Test Subject: Mathematics Time:30 min F.M.: 50 Class: Four Group A (Objectives) 1. Choose the correct answer from the given alternatives and tick the correct answers. (5×1=5) a) A dot represent a ___________. i) Triangle ii) Rectangle iii) Point b) A ray has _______ end points. i) 1 ii) 10 iii) 100 c) Largest five digit number is _________________ . i) 12345 ii) 54321 iii) 99999 d) represent a ___________. i) Triangle ii) Ray iii) Rectangle e) A line segment has _______ end points. i) 100 ii) 2 iii) 9 2. Match the following: 5×1=5 a) Group 'A' Group 'B' Triangle ABC Line Rectangle Right angle 90’ Angle PQR 4 sides 3. Write True of False. (5×1=5) a) Point is the smallest shape. b) Triangle has four sides. c) Ray has one end point. d) Quadrilateral has 3 sides. e) Shape of ice-cream is cone. --73--

Mathematics 4. Fill in the blanks. (5×1=5) a) We use ____________ to measure length of line. b) The angle whose measure is greater than 900 and less than 1800 is called _____________. c) We use ____________ to measure angle. d) The angle whose measure is less than 900 is called _____. e) 100 ones = 1 hundred. _______ . (Subjective) Group B (5×2=10) 1. Write two names of given angle. ∢ ________________ ∢ ________________ 2. Identify the following angles as acute, obtuse or right. i) ii) 3. How many line segment are there in given figures. i) ii) 4. Count the line segment and write in boxes. i) ii) 5. Make largest and smallest number by using following digit. 4, 7, 2, 9, 8 Largest Smallest Group C (5×4=20) 11. Draw an angle of 750. --74--

Class-4 12. Write the number of faces, edges and vertices of the following objectives:- i) ii) Faces : 5 Faces : _____________ Edges : _______________ Edges: ______________ Vertices : ______________ Vertices: _____________ 13. Write the number names for the followings:- i) 24809 = ________________________ ii) 90024 = _______________________ 14. Draw the place value chart (national) for the numeral 964328. 15. Draw the international place value chart for the number 78465949 . Stay Home stay safe Self-Evaluation Test Subject: Four Time: 2hrs 30 min F.M.: 100 Group A (Objectives) 1. Choose the correct answer from the given alternatives and tick the correct answers. (10×1=10) a) represent a ___________. i) Triangle ii) Rectangle iii) straight line b) The arrowhead at the one ends is in a _____________. i) Road ii) Book iii) Ray c) A ray has _______ end points. i) 100 ii) 2 iii) 9 d) Largest five digit number is _________________ . i) 4 ii) 1111 iii) 9999 e) 999 + 1 = ___________. ii) 999 ii) 1000 iii) 1 f) 3 X 1000= __________ i) 3 ii) 3x1 --i7ii5)-3- 000

Mathematics g) 4556-4556 = ___________. i) 0 ii) 4556 iii) 1 h) 5659+1 = ___________. i) 5660 ii) 559 iii) 0 i) 452 + 214 = _________________ i) 767 ii) 454 iii) 666 j) The set notation of ������������ belongs to the set A' is __________ i) ������������ ∈ ������������ ii) ������������ ∉= ������������ iii) ������������ = ������������ 2. Match the following: 10×1=10 a) Group 'A' Group 'B' Cube 23000 Twenty three thousands 1,00,000 One 2 Only one even prime number Ray b) Group 'A' Group 'B' The symbol of subtraction 4505 4504-0 7 belongs to the set A 2434+123 set of fruits � � 100000 7 ∈ ������������ 2557 3. Write True of False. (10×1=10) a) The arrowhead at two end is in a straight line. b) The correct name of is ray BA. c) Shape of book is cuboid. d) Prime number starts from 2. e) Place value of 4 in 4237 is 3000. f) 2,4,6,8 are the even number. g) '+' is the sign of addition. h) 402-8 = 394. i) We can make a set of flowers. j) If A = {������������, ������������, ������������}, ������������ ∉ ������������. --76--

Class-4 4. Fill in the blanks. (10×1=10) a) The ___________ point of the two rays corners is called vertex. b) a point is a ________________ shape. c) 1 more than 100 is ________________. d) We write thirty thousand as _________________. e) Three factors of 6 are ______________________. f) _________________ is the factor of every number. g) 646 + 213 = ___________. h) 894-232 =_____________. i) 22 - ________ = 15 j) {������������, ������������, ������������, ������������, ������������}, a is ___________ to the set U. 859, 1, belongs, 1, 2 and 3, common, smallest, 101, 7, 30000, 662 (Subjectives) Group B (10×2=20) 1. Draw a line segment of 6 cm. 2. How many line segments are there in given figures? i) ii) 3. Find the perimeter of the given figure. 4. Complete the following. 546421 L. T. Th. Th. H. T. O. 5. Write the place value of circled digit. i) 9 9 8 7 8 6 = ____________. --77--

Mathematics ii) 2 6 3 2 4 =_______________ 6. Addition 36961 7. Subtraction 76459 +21038 –54256 8. Subtract 45646 from 98969. 9. Make a set of any four flowers. 10. List the elements of the following set. Group B (10X4=40) 11. Draw an angle of 600. 12. Write the number of faces, edges and vertices of the following objectives:- i) ii) iii) ___________ ____________ ______________ iv) _______________ 13. Identify the following angles as acute, obtuse or right. i) ii) iii) iv) --78--

Class-4 14. Make longest and smallest number by using following digit. i) 7,5,9,1,3 ii) 3,9,4,2,1 Largest = __________ Longest = ____________ Smallest = _________ Smallest = ____________ 15. Write the number names for the followings:-. i) 38409 ii) 90240 16. Complete the following :- 30951 17. Addition:- 11422 18. Subtraction:- 947563 21804 –83675 +10083 19. The difference of two numbers is 45262. If the greatest number is 190450, find the smaller number. 20. Describe the following sets. i) {������������������������������������������������������������������������������������, ������������������������������������������������������������������������������������������������, ������������������������������������������������ℎ} = {______________________________________________} ii) {������������, ������������, ������������, ������������, ������������} = {______________________________________________} Thank-you --79--

Subject : Science Day-1 Chapter: Different types of Animal Activity -1 You can see different man made things, different plants and different animals around you. Now observe different kinds of animals. Among them some are bigger in size while some are smaller in size. Elephant, rhinos, buffaloes, cows are big and ant, mosquito, flies are small. There are also very small animals which we cannot see from our naked eyes. We need special instruments to see those tiny animals. The largest animal is blue whale which is found in ocean and amoeba is small animal. All these animals are classified into two types. They are vertebrates and invertebrates. Activity-2 1. Observe different animals around you and write shape, size and places where they live. Day-2 Activity-1 Vertebrates : Vertebrates are those animals which have backbone in their body. Big animals like buffalo, cow, horse, monkey, elephant, birds etc. all are vertebrates. Even we humans have also backbone, so we can stand straight, run here and there etc. Backbone is situated at back side of your body and is connected with your head. Functions of bones: If we do not have bones, our body will be heap of muscles only. We could not sit, stand and run without bones. Bones provide size to our body. They also give shape to our organs. Bones also protect our internal organs. All vertebrates are not of same kind. They have different – different characters. So vertebrates are also divided into five different groups. These groups are Mammals, Birds, Reptiles, Amphibians and Fish. Activity-2 1. What are vertebrates? Give examples. --80--

Class-4 Day-3 Activity-1 Fishes : Fishes are the vertebrates that live in water only. The characters of fishes are given below: a. Their skin is generally covered with scales. b. They breathe through gills. c. They lay eggs in water. Examples are Tuna, Salmon, Trout, Carp, Rohu etc. Activity-2 1. Write two characters of Fishes. Day-4 Activity-1 Amphibians : Amphibians are those animals which live both on land and water. The character of amphibians are given below: a. They breathe through skin and lungs. b. They have wet and soft skin. c. They are eggs laying animals. Examples: Frog, Toad, Hyla etc. Activity-2 1. Write two characters of Amphibians. Day-5 Activity-1 Reptiles : Reptiles are those animals which live on land only. The characters of reptiles are: a. They are egg laying animals. b. They breathe through lungs. c. Their body is covered with hard and dry scales. Example: Snake, Garden lizard, Python, Tortoise etc. Activity -2 1. Write two characters of Reptiles. Day-6 Activity-1 Birds : Birds are those vertebrates which fly on air for more time in their life. The characters of birds are: a. They breathe through lungs. --81--

Science b. They are egg laying animals. c. Their body is covered with feathers. Example: Sparrow, Crow, Pigeon, Vulture, Parrot etc. Activity-2 1. Write two characters of Birds. Day-7 Activity -1 Mammals Mammals are the most advanced animals of vertebrates. They have most developed sense organs. The characters of mammals are: a. They breathe through lungs. b. They give birth to babies c. Mammals (females) feed milk to their babies. Examples: Human, Bat, Dolphin, Rat. Dog, Cat etc. Bats are the mammals which can fly. Platypus are the mammals that lay eggs. Activity -2 1. Write two characters of Fishes with examples. Day-8 Activity -1 Invertebrates : Those animals which do have backbone are called invertebrates. Small animals like earthworm, snail etc. are invertebrates. Most of the invertebrates have soft body while some has hard shells. Most of the invertebrates are small animals. Like vertebrates, invertebrates are grouped into many categories. Some of the categories are described below: Worms : There are different types of worm found on the earth. Worms are also divided as flatworms, roundworms and segmented worms. Activity-2 1. What are invertebrate animals? Give examples. --82--

Class-4 Day-9 Activity -1 Flatworms : The flat shaped invertebrates are called flatworms. They are also called flukes. The character of flatworms are as follows: a. They have ribbon shaped body. b. Mostly of them are parasites. c. They are found in animals and human body. Examples are Tapeworm, Liver fluke etc. Activity -2 1. Write two characters of flatworms with example. Day-10 Activity -1 Roundworms : Those invertebrates which have thin, round and long body are called roundworms. The character of roundworm are as follows: a. They are round in shapes and found in fresh water and soil. b. They have long and thin body. c. Many of them can see through our eyes. Examples are Hookworm, Pin worms etc. Segmented worms : Those invertebrates whose body is segmented are called segmented worms. The characters of segmented worms are as follows: a. Their body is divided into different segments. b. They have moist skin. c. Some are parasites in nature. E.g. earthworm. Activity-2 1. Write two characters of roundworms with examples. 2. Write two characters of segmented worms with example. Day-11 Activity-1 Insects : This group of invertebrates which contains almost all types of insects. The characters of arthropods are as follows: a. They have six legs. b. They have antenna as sense organs. c. They have jointed legs. Examples are Butterfly, Prawn etc. Activity-2 1. Write two characters of insects with examples. --83--

Science Day-12 Activity-1 Snails : Those vertebrates which have soft skin and body is covered with shells are called snails. The characters of snail are as follows: a. They mostly live in water. b. They breathe through gills c. Their body is covered with shells. Examples are Snail, Octopus, Slug etc. Activity-2 1. Write two characters of Snails with examples. Day-13 Activity-1 Animals reproduce by two ways; by laying eggs and by giving birth to young babies. Egg laying Animals : All invertebrates lay eggs to reproduce. Insects, snails and worms all reproduce by eggs. Vertebrates like birds, reptiles, birds and amphibians also lay eggs. The female of the vertebrates lay egg. They egg on nest, soils and water. After some day, new babies come from eggs. Inside eggs, they get food from eggs. New babies are born from yellow part of eggs. Some animals lay hundred number of eggs while some lay few number of eggs. You may have seen hens laying 4 to 5 eggs while insects laying hundreds of eggs in plant’s leaf. Hens and birds sits on their eggs until new babies come out. They do like that to keep their eggs warm. Heating of eggs develops chicks inside the egg. Frogs and fishes do not sit above their eggs because their eggs do not need heat. A chicken is born after 21 days of laying eggs. Animals like fishes and frogs lay eggs on water. Activity-2 1. Give some examples of egg laying animals. 2. Why hens and birds sit on their eggs? Day-14 Activity-1 Birth giving animals : Only mammals give birth to young babies directly. The babies are developed inside female body where male and female eggs are --84--

Class-4 mixed and fertilized. After some time, the fertilized egg becomes baby and come out of female’s body as new baby. The part of female where baby develops is called womb. Inside womb, baby get food from mother. After the baby is born, it is fed milk by its mother. Activity-2 1. Give examples of egg laying animals. 2. From where baby gets food inside mother’s worm? Day-15 Activity -1 1. The world’s largest animals is…………….. 2. The hard cover of an egg is called…………… 3. Bat is a ………………. 4. Fishes breathe through ………………. 5. Snails have ……………….. for movement. Activity-2 1. Dolphin is a ……………….. 2. Vertebrates are divided into ……………….. groups. 3. ………….. is an example of reptile. 4. Earthworm belongs to …………. group. 5. Grasshopper is a ………… Day-16 Chapter: How animals live in nature Activity-1 The place where animal live is called habitat. Animals live in different habitats. These habitats are different and many in number. This habitat can be land or water or both. Land habitats are also of different types and water habitat are also many in number. Land habitats are desert, cold climate, shady climate etc. and water habitats are pond habitat, river habitat, sea habitat etc. Animals living in one habitat cannot live in another habitat. For eg. Yak found in Himalayan region cannot live in terai of our country. All animals need right temperature and suitable place to live in. They should get food, protection from enemy and warmth to their babies. --85--

Science 2. Why do animals need habitat? Activity-2 1. Define habitat. Day-17 Activity -1 Characteristics of land animals : Different types of animals live in land. They adjust themselves in order to live in their habitats. The land habitats are also of different types; e.g. desert, forests etc. Desert animals : Desert is a very hot place. There is very less rainfall. It is very hot at day and very cold at night. The characters of animals living in desert are: a. They can walk long time without water. b. They can walk on sand filled desert. c. They store fats in their body and get energy. Examples of desert animals are camel, lizards etc. Activity-2 1. Write two characters of animals living in desert. Day-18 Activity-1 Carnivorous Animals : Those animals which eat flesh of other animals are called carnivorous animals or carnivores. The character of carnivores are: a. They have strong mouth to tear flesh. b. They can see far objects. c. They can shallow the whole prey also. Examples of carnivores are tiger, eagle, shark etc. Herbivorous Animals : Those animals which eat grass only are called herbivorous animals or herbivores. The character of herbivores are: a. They only eat plants, grains and grass. b. They have sharp cutting teeth. c. They generally chew curds. E.g. Cow, buffalo. Chewing curd : Herbivores like cow, buffalo etc. cut the grasses very fast and shallow them. When they rest, they bring back the same food in their mouth and chew again into smaller pieces. --86--

Class-4 Activity-2 1. Define herbivores and carnivores. 2. What do you mean by chewing curd in animals? Day-19 Activity-1 Cold climate animals : The animals which live in Himalayan regions or extremely cold regions are called cold climate animals. The characters of cold climate animals are: a. They have thick hair in their bodies. b. They have thick layer of fat under their skin. Examples are Chyangra, yak, polar bear, snow leopard etc. Birds in the cold regions travel to warm places during winter. They return to their places when it is warm. This movement is called migration. Similarly, we do not see frogs, snake etc. in winter season. They do not migrate but make a hole in soil and sleep in all winter. The process of sleeping in winter season to protect from cold is called hibernation. Activity -2 1. What is migration and hibernation? 2. Give two examples of animals that go for hibernation. Day-20 Activity-1 Birds : You can see birds flying in the sky and sitting in the trees. You might have heard birds singing too. You may have heard cuckoo singing Kafal Pakyo also. Birds are wonderful animals. Some are very attractive in looking also. Birds fly here and there but we cannot fly. Birds can fly due to their light weight and shape of their body. They also have wings to fly. Birds also have hollow bones which makes birds light and easy to fly. There are some birds which cannot fly. Ostrich, Kiwi etc. cannot fly because their wings are not developed. Activity -2 1. How can birds fly? 2. List the birds you see yesterDay-in your area. --87--

Science Day-21 Activity -1 Arboreal Animals : Animals which live in trees are called arboreal animals. They have strong and long legs to catch the branches of tree easily. They also have strong chest muscle to jump from one trees to another trees. Some animals may have long tails. Examples of arboreal animals are monkey, squirrel, langoor etc. Some animals have adhesive pad on their feet which makes them easy to climb walls and ceilings. E.g. Wall lizard. Activity -2 1. What are arboreal animals? Also give examples. Day-22 Activity-1 Water Animals : Those animals which live on water are called water animals. Different kinds of fish live in water. Some live in rivers and ponds, while some live in seas and oceans. Fish have fins to swim in water. They breathe through gills. Gills absorb oxygen from water. Not only fishes many animals are depended on water for their living. Duck, crocodile, penguin, frog etc. also live near water. These animals can swim in water and get their food from it. The duck and frog have flat feet which helps them to swim in water. Birds like herons, spoonbills, pelicans etc. are called wading birds. They have long legs and beaks. These birds in wade in shallow water to find their foods. Activity -2 1. What are water animals? Give examples. 2. Name the organ of fish that helps in breathing in water. 3. What are wading birds? Day-23 Activity-1 Camouflage : You may have seen army with green dresses and carrying grass on head and bodies in movies. Why they wear so? Discuss with your family and friends. Army have wear that type of dress so that they will be unnoticed by enemies. Like these some animals also have special character, so that they will be safe from enemy animal. --88--

Class-4 The colour of some animals match with the environment. Some animals even have ability to change their body’s colour same as outside. The property of animals to change their colour as outer surrounding is called camouflage. This property of animals helps to protect the animals from enemy. Chameleon is a kind of lizard which changes its color according to surrounding. Similarly, grasshopper is green in colour and lives in grass so we cannot see it easily. Giraffe, zebra, deer etc. hide in surrounding to be protected from prey while tiger hides on surrounding to wait the prey. Activity-2 1. Define camouflage. 2. Why do animals have this property? Day-24 Activity-1 1. Camels have …………….feet. 2. Grass eating animal have strong …………teeth. 3. The place where animals live is called………….. 4. ……….is a bird that cannot fly. 5. Yak lives in………… place. Activity -2 1. Fresh eating animals have sharp ………teeth. 2. The habitat of tiger is …………. 3. Monkey is ………….animal. 4. ………..can swallow its prey at a time. 5. Polar bear have ………fur on their body. Day-25 Chapter: Matter Activity-1 There are various types of substances around us like air, water, soil, stone, animals, plants, paper, oil, candle, shampoo etc. some things we can see and feel while some things we cannot see but feel. Stone, animals etc. can be seen as well as can be felt. The things which we can feel only is air. --89--

Science Whatever the substances are, all of them are matter. Anything that has weight and occupies space is called matter. Light, shadow, sound etc. do not have weight and do not occupy space. They are not matter. State of matter : Matters are classified into three state. They are solid, liquid and gas. Solid, liquid and gas are three state of matters. Solid are ice, iron, utensils etc. Liquids are water, honey etc. Gases are air, smoke etc. Activity -2 2. What are three states of matter? 1. What is matter? Day-26 Activity -1 Solid : Those matter which have fixed shape and occupy space are called solids. Stones, paper, nail, match box, geometric box, soap, shampoo bottle, ink pot etc. All solids are not same in structure. Solids have different properties as follows: a) Some are hard or soft. b) Some are opaque or transparent. c) Some are combustible or non-combustible. Activity-2 1. Define solid. Give examples of solid. 2. Write properties of solid. Day-27 Activity-1 Liquid : Those matter which occupies space but do not have fixed shape are called liquids. Their shape is same as the shape of vessel where it is kept. Water, oil, shampoo etc. The properties of liquid are : a) Some liquid have colour or no colour. b) Some liquids can burn or do not burn. c) Some liquid have smell or do not have smell. Activity-2 --90-- 1. Define liquid. Give examples. 2. Write properties of liquid.

Class-4 Day-28 Activity-1 Gas : Those matter which have fixed weight but does not occupy the same space are called gas. The shape of the gas also changes according to the shape of vessels. Air is the gas state of matter. Air contains oxygen, nitrogen, carbon dioxide etc. Animals get oxygen from air. Plants also get carbon dioxide from air. Air has a property of being compressed. You have seen cylinder gas at your home. There is a gas inside cylinder. Gas is compressed and fill in cylinder. Similarly you may have seen gas lighter also. In gas lighter, gas is compressed and fill. The property of liquid and gas by which they flow is called fluid. Activity-2 2. Define fluid. 1. Define gas. Give some examples. Day-29 Activity-1 Changing of state of matter : A solid can be change into liquid and liquid into gas. Similarly gas can be change into liquid and liquid into solid. When an ice cube is heated, it changes into water. Again when water is heated, it changes into vapour. When the vapour is cooled, it changes into water. Again when water is cooled, it changes into ice cube. The process of changing one state of matter into another state is called change of state. Changing solid into liquid (Melting) : When you put ice cubes in your hand for longer period of time, the ice starts converting into water. When you hold ice cream in your hand at sunshine for longer period of time, ice cream starts changing into liquid. The process of converting solid into liquid on heating is called melting. Activity-2 1. What is melting? Give examples of melting. 2. Define change of state. --91--

Science Day-30 Activity-1 Changing liquid into gas (Vaporization) : When you boil the water for some time and stop boiling, you will find that the amount of water is decreased. Also during boiling you will notice that a gas is rising from the liquid, The gas rising from liquid while the liquid is boiling is called vapor. The process of changing of liquid into vapor using heat is called vaporization. Activity-2 1. Define vaporization. Give one example of vaporization. Day-31 Activity-1 Changing gas into liquid (Condensation) : We have read already that when solid is heated, it melts and change into liquid. When liquid is heated, it vaporizes and changes into gas. Similarly when we cool down the gas, it changes into liquid. The process of changing the gas into liquid on cooling is called condensation. Activity -2 1. Define condensation. Give examples of condensation. Day-32 Activity-1 Changing liquid into solid (Freezing) : We have read already that when solid is heated, it melts and change into liquid. When liquid is heated, it vaporizes and changes into gas. Similarly when we cool down the gas, it changes into liquid. And sequentially, when we cool the liquid, it changes into solid. The process of changing the liquid into solid on cooling is called freezing. --92--

Class-4 Activity-2 1. What is freezing? Day-33 Activity-1 1. There are ……….states of matter. 2. Liquids do not have fixed …………. 3. ……….is changing a liquid into solid on cooling. 4. Liquids and gases are called………… 5. ……….is space occupied by a body. Activity-2 1. We can identify perfume by ………….. 2. …………is fourth state of matter. 3. The changing of gas into liquid by cooling is called…………… 4. Solids have fixed …………….. 5. The cloud changes into rain because of ………… Day-34 Chapter: Changing Earth Activity-1 You may have different types of clothes in your wardrobe. Some clothes are woolen and some are cotton clothes. You wear woolen clothes in cold to make you warm while you wear cotton clothes in hot to make you cool. You can select the type of clothes you wear by looking at the condition of the outside also. If it is very sunny outside, you wear thin clothes and if it is raining outside, you carry umbrella and wear warm clothes. Even in a single day, you may see the condition of outside is changing. Sometime it may be windy, sometime it may be hot, and sometime it may be rainy. The condition of atmosphere of a place at a particular time is called weather. Activity-2 1. Define weather. 2. List the names of clothes you wear in winter season. --93--

Science Day-35 Activity -1 Sunny weather If the sky is clear and there is bright sunshine, it is a sunny weather. We feel very hot during sunny day. In the sunny day, there is cloud in the sky. During mid-day-it is hotter. During sunny day, we mostly wear thin clothes and stay inside. In school we sit under the fan. Our clothes dry fast in sunny days. Farmers dry grains in sunny day. Activity -2 1. What type of weather is sunny weather? 2. What do you do in sunny day? Day-36 Activity-1 Cloudy day : The day when the clouds cover the sun is called cloudy day. The cloudy day are cool than sunny day. If we see black clouds all over the sky, rain may fall on that day. Cloudy dayare colder in winter season. Cloudy day in summer may bring rainfall. So cloudy day are good during summer. If the sky becomes cloudy in night, then the night will be warmer than clear sky day. Activity-2 1. Define cloudy day. 2. Why nights are warmer in cloudy day? Day-37 Activity-1 Rainy Days : The day on which rain falls during the whole day is called rainy day. Rainy days occur in monsoon seasons mostly. But rain can fall in any seasons. In monsoon, heavy rainfall occurs and in other seasons rainfall is light. Rainfall is very important for farmers. Farmers can increase crop production if rainfall mostly occurs. --94--

Class-4 Rainy day is colder than other days. We wear woolen clothes during rainy days.We should take umbrella with us while going anywhere in rainy days. Pokhara is the place of Nepal where more rainfall takes place. Activity-2 1. Name the place where more rainfall takes place in Nepal. 2. Why farmers are happy in rainy days? Day-38 Activity-1 Snowy Days : Snow fall takes place in cold places only. When snow starts to fall due to decrease in temperature, the day becomes snowy day. Snow fall takes place during winter season only. We should wear thick and woolen clothes in snowy day. People become happy when snow falls. People play with snow also. We can also play snow but we should be very careful. We should wear gloves before touching snow. We should wear shoes while walking in snow. We should drinks hot drinks and stay inside our house during snowy day. Activity-2 1. What should we do in snowy day? 2. Where snow fall takes place? Day-39 Activity -1 Windy day : Blowing of very fast air is called wind. When air starts to blow faster than normal, then the day is called windy day. Windy day is very dangerous, so we should stay inside our house during windy day. Wind may be hot or cold. Hot wind is called Loo. Cold air is also dangerous as people may die due to cold wind. Strong wind can blow house’s roof, breaks tree and cause many damages. Wind with rain is also dangerous. It causes storms. Storms take people’s life yearly in the world. Windy days are not welcomed. Slow wind are pleasant. They are called breeze. --95--

Science 2. Why wind with rain is dangerous? Activity-2 1. Define wind. Day-40 Activity -1 Pleasant day The day which is very cool, have clear sky, have gentle breeze is called pleasant day. All people are happy with pleasant days. During pleasant day, people prefer to go outside of house and roam here and there. People go hiking these days. People got to picnic and tour in these days. Our festivals dashain and tihar mostly have pleasant days. During this time, we love to play and gather outside of our home. Activity-2 1. Why do people like pleasant days? 2. What type of day is pleasant day? Day-41 Activity-1 Our Seasons : We know that all days in a year are not of equal length. Some days are longer while some days are shorter. During winter, days are shorter and during summer days are longer. During some time, we see flowers all around us while during some other days we don’t see leaves in a plant also. These all things happen due to the change in seasons. We have four seasons: Summer season, spring season, autumn season and winter season. Activity-2 1. Name four seasons. Day-42 Activity-1 Causes of season : Our planet earth revolves around the sun. it revolves around the sin in 365 days. 365 days is a year. The earth revolves sun in a path. The path on which earth travels around the sun is called orbit. The orbit is oval. --96--

During the revolution changes in the season takes place. Class-4 seasons summer autumn winter spring March, April, North June, July, September, December, May hemisphere August October, January, September, October, November February November South December, March, April, June, July, hemisphere January, May August February Activity-2 2. Why changes of season takes place? 1. What is orbit? Day-43 Activity-1 Summer season : The hottest season of the year is called summer season. In Nepal, rain fall occurs heavily in summer season. In poles, rainfall do not occur in this season. The northern hemisphere receives direct sun light in this season, so it is very hot in north hemisphere. In our country farmers plant paddy and harvest maize in this season. We see greenery around us in this season. Autumn season : The autumn season comes after summer season in northern hemisphere. In this season plants shed their leaves. The colour of leaves also changes in this season. In this season north and south hemisphere receive equal sunrays. The day and night are also of equal length in this season. Activity-2 1. What happens in summer season? 2. What happens in autumn season? Day-44 Activity-1 Winter season : The coldest season of the year is called winter season. In the poles, there is heavy rainfall and frost. Trees are naked in this season. The sun rays falls slantly in our country. The days are shorter and nights are longer in this season. Very few animals are seen outside. December 22 is the shortest day in the northern hemisphere. --97--

Science Spring season : Spring season comes after winter season in northern hemisphere. The snow starts melting in the poles. Plants again start to bloom. Animals produce new ones in this season. In our country Nepal the days become cool in this season. It is also starting of summer season. The days starts becoming longer and night start becoming shorter. Activity -2 1. Why it is cold in winter season? 2. Which season shows starting of summer season? Day-45 Activity-1 1. We were …….clothes in summer seasons. 2. Cloudy days in winter are ……….. 3. The spinning of the earth is called………….. 4. Cold and gentle wind is called ……….. 5. …………season is good for farmers. Activity-2 1. Prepare a chart showing month and season in southern hemisphere. 2. Draw a diagram showing change in season with labelling. Day-46 Chapter: Keeping Clean Activity -1 We should know good personal hygiene and good health behavior. Cleanliness is such a thing that makes you healthy as well as you look tidy and smart. You should start to keep healthy from this stage of life so that you will easily develop a habit of being healthy and smart. In future, you will be socially adaptable too. If you adopt a good personal hygiene then, in future not only you are healthy nut also help to prevent spreading disease too. Activity -2 1. Why we should keep ourselves clean? --98--

Class-4 Day-47 Activity-1 Taking care of eyes : Eyes are very important sense organs. We see this beautiful world through our eyes. So, we should take care of our eyes very properly. If our eye is not properly cleaned, we may loss our vision and may develop different disease in our eyes. We should also be very careful during the cleanliness of our eyes. We should follow following points: a) We should protect our eyes from external injury also. b) We should wash our eyes regularly with clean water. c) We should not rub our eyes. d) We should not watch TV too close. Activity -2 1. Write few points to keep our eyes clean. Day-48 Activity -1 Taking care of ears : Ears are important sense organs. Ear helps us for hearing. We should take care of our ears by following ways: a) We should avoid loud music. b) We should not put anything inside our ear. c) We should clean our ear using ear buds. d) We should wash our ear externally with clean water. Activity -2 1. How can we take care of our eyes? Day-49 Activity-1 Taking care of skin : Skin is outer covering of our body. It protects our body. We feel with the help of skin. We should take care of our skin by following ways: a) We should have regular bath. b) We should dry our skin with clean towel. c) We should wash our hair with water and shampoo. d) We should not keep our skin dry. --99--

Science Activity-2 1. How can we take care of our skin? Day-50 Activity-1 Taking care of nose : Nose is a important sense organ. It helps us in smelling and taking air. We should take care of our nose by following ways: a) We should not put finger in our nose. b) We should use hanky for running nose. c) We should not blow our nose hard. d) We should wear masks in dusty places. Activity-2 1. How can we take care of our nose? Day-51 Activity -1 Taking care of teeth : Teeth is an important part of our mouth. Teeth helps in chewing the food we eat. We should take care of our teeth by following ways: a) We should brush our teeth daily. b) We should not eat sweets food in more quantity. c) We should use soft brush while brushing the teeth. Activity -2 1. How can we take care of our teeth? Day-52 Activity -1 Taking care of hands and nails : We use our hand for doing different sort of works. While doing works, our hands become dirty. We should take care of our hands by following ways: a) We should keep our hand clean. b) We should wash our hand before and after the meal. c) We should wash our hand before and after toilet. d) We should wash our hand with soap and clean water. --100--