MATHEMATICS Y1 - PART 1

3 How many buttons are there in the blue jar?

The number of
buttons in the blue
jar is more than the

orange jar.

The number
of buttons in the
blue jar is less

15 ? 25 than the red jar.
The buttons in the blue jar is about 20.

SELF-TEST 2 Estimate the number of
1 Estimate the number of bottles of pomegranate
juice that can fit into the
tomatoes in the blue box. box.

30 ?

1.7.1 • Explain to pupils that the words “about”, “approximate”, “more than” and
“less than” must be used when making estimation.
44
• Carry out a competition to estimate the number of candies in a container.
• Provide more questions in the form of worksheets or question cards.

AB page 59

RECOGNISE ROUND OFF

1 Help the rabbit to get the carrot. Round off 22 to the
nearest ten.

Which carrot Carrot at hole
will the rabbit 30 is far. Carrot at

choose? hole 20 is near.

20 21 22 23 24 25 26 27 28 29 30

20 21 22 23 24 25 26 27 28 29 30
22 is nearer to 20 than 30.

22 when rounded off to the nearest ten becomes 20.
Rabbit gets carrot at hole 20.

What will happen if the
rabbit is at hole 28?

• Explain that round off is a process of determining number to the nearest place value.
1.8.1

45

2

64 65 66
63 67
60 61 62 68
69 70

a Round off 67 to the nearest ten.

60 67 70

67 is nearer to 70.
67 when rounded off to the nearest ten becomes 70.

b Round off 65 to the nearest ten.

60 65 70
65 is in the middle of 60 and 70.

65 when rounded off to the nearest ten becomes 70.

Round off 74, 85 and 98
to the nearest ten.

1.8.1 • Emphasise to the pupils that the number in the middle of two consecutive
tens are rounded off to the larger ten.
46

are rounded off to the nearest ten?

80 81 82 83 84 85 86 87 88 89 90

80 81 82 83 84 85 86 87 88 89 90

85, 86, 87, 88 and 89 are near to 90.
85, 86, 87, 88 and 89 become 90 when
they are rounded off to the nearest ten.

Can 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9
be rounded off to the nearest

ten? Discuss.

SHARPEN Select the number cards which become
YOUR 60 when rounded off to the nearest ten.
MIND
71 59 63 74 55 65

• Emphasise that round off is a way of getting a quantity or an estimated value.

1.8.1
AB pages 60 - 62

47

SELF-TEST

1 Round off the numbers to the nearest ten.

40 44 45 50
a 44 44 is rounded off to
.

b 45 45 is rounded off to .

2 Round off the numbers to the nearest ten.
a 6 b 79 c 25 d 84

3 Choose the numbers that become 10 when they are
rounded off to the nearest ten.

15 11 14 19 8 17

4 What are the numbers that become 30 when they
are rounded off to the nearest ten?
33 29 24 39 31 26

1.8.1 • Surf https://www.superteacherworksheets.com/rounding/rounding-rockets-10s_
TZQWQ.pdf
48
• Provide more questions in the form of worksheets or question cards.

SOLVE THE PROBLEMS

1 Asma wants to form
two-digit numbers
using the number
cards. How many
numbers can be
formed?

Method Draw a table.

Write the digit of tens.
Then, write the digit of ones.

Number begins Number begins Number begins
with 7 with 5 with 2

75 57 27

72 52 25

There are 6 numbers altogether.

What is the largest number?
What is the smallest number?

1.10.1 • Guide the pupils to build numbers from different number cards. Encourage them
to determine their own form of tables such as how many columns, rows and labels
that need to be made.

49

2 Ali has 45 marbles.
He has 5 more
marbles than Kumar.
How many marbles
does Kumar have?

Method Draw a diagram. 5 45
Ali’s marbles more

Kumar’s marbles 5
Kumar’s marbles are 5 less than 45. less

Count back 5 steps from 45.

40 41 42 43 44 45

Kumar has 40 marbles.

1.10.1 • Help the pupils to understand the information in the question. Emphasise to the
pupils that they only need to draw a diagram that has important information to
50 solve the problem.

3 Ramesh and Maya are talking.

Ramesh, my body Maya, my body mass is
mass is 30 kg. more. If I rounded off my

body mass, it is also 30 kg.

What is Ramesh’s possible body mass?

Method Guess and check.

Test 1 31 31 is rounded off to 30.
Test 2 32 32 is rounded off to 30.
Test 3 33 33 is rounded off to 30.
Test 4 34 34 is rounded off to 30.
Test 5 35 35 is rounded off to 40.

Ramesh’s possible body mass is
31 kg, 32 kg, 33 kg, or 34 kg.

1.10.1 • Guide the pupils to round off the numbers based on the information given in the
questions so that they do not make random guesses.

51

4 Mei Lin wants to make a bracelet. She uses the beads as
below.

What is the pattern of Mei Lin’s bracelet?

Method and 2 repeatedly.
Mei Lin arranges 4

The pattern of Mei Lin’s bracelet is 4, 2, 4, 2, 4, 2.

Make your own bracelet.
Talk about the pattern.

SELF-TEST

I have a number. The digit value of tens is between
70 and 90. The digit value of ones is 4 more than 5.
What is my number?

1.10.1 • Teachers need to emphasise the steps to solve the problem.
• Provide more questions in the form of worksheets or question cards.
52
AB pages 63 - 66

MY Numbers Participants In pairs.
PROJECT expert
Materials Task table
and pencils.

Method

1 Write a two-digit number in numerals and words.

2 Complete the task table.

Task table

Number
1. How many tens?
2. What is the digit value of tens?

3. What is the digit value of ones?
4. Write a number that is larger than the number formed.
5. Write a number that is smaller than the number formed.
6. What is a number that is 10 less than the number formed?
7. Round off the number to the nearest ten.

3 Exchange the task table with your partner.

1.2.2(iii) • Prepare sufficient task tables for all pupils.
1.3.1
1.6.1 • Ask the pupils to check their friend’s answers.
1.8.1 • Use the example above to create another task.

53

Whose number Participants 3 pupils and
is larger? 1 referee.

Rules Materials 2 set of number
cards, 0 to 9.

1 Distribute the number cards 2 Create the largest
randomly to each player. number of two digits.

4 Jot down the marks.

the larger number will Round Name Marks
get higher marks. 1
Devi 15
Devi gets the Isma 10
highest mark. Kumar 5

2

3

5 Repeat steps 1 to 4 until all the cards are finished.

1.2.2(iii) • Provide sufficient number cards. Assign the referee to give them to the players and
collect the number cards used.
54
• Instil moral values such as trust and cooperation while carrying out the activity.
• Give 15, 10 and 5 marks for the correct arrangement of numbers. 0 mark if wrong.

AB pages 67 - 68

2 ADDITION AND

SUBTRACTION

• Guide the pupils to determine the number of objects in the stimulus picture. Relate

2.1 the number of objects with addition and subtraction operations. For example, the
number of girls and boys, number of toy cars which are not in the container and

so on.

55

RECOGNISE ADDITION

1 There are 4 balls

in the basket.
I put
1 more
ball.

How many balls altogether?

4 balls and 1 ball make 5 balls altogether.
41

2.1.1 5
4 add 1 make 5.
56
There are 5 balls altogether.

• Guide the pupils to understand the concept of addition using simulation and
vocabulary related to the concept of addition such as combine, group, altogether,
total and so on.

• Explain that addition is the sum of any two numbers.

2 How many cats are there altogether?

3 cats are playing.
2 more cats are joining them.

3 and 2 make 5.
3 add 2 is equal to 5.

When we add, the number
will be more.

Number 3+2=5
sentence

add + = is equal
to

There are 5 cats altogether.

2.1.1 • Emphasise to the pupils the meaning of the symbols for “addition” and “is equal to”.
2.1.2 • Carry out the activities using concrete materials and relate it with pupils’ real life to
2.1.3
enhance their understanding.
AB pages 69 - 72 • Explain that number sentence is the sentence written in numerals and symbols.

57

3 Amir has 6 marbles. Lau gives another 2 marbles.
How many marbles does Amir have altogether?

6+2=

Method 1 Method 2

Count all.
1, 2, 3, 4, 5, 6, 7, 8.

1 2345678

6+2= 8
Amir has 8 marbles altogether.

4 What is the total number of ?
0+3=

0
3

3

0+3= 3

The total number of is 3.

2.2.1 • Expose the pupils to various methods to solve addition operation. Use picture cards
to help them in mastering the skills of addition.
58 • Guide the pupils to use combination of numbers for addition.
• Explain that when 0 is added to a number, the answer is the number itself.

5 There are 4 outside the box.
The total of is 7. How many
are there inside the box?
4+ =7

Count on from 4.
5, 6, 7. Get 3 steps.

0 1 23456 7

4+ 3 =7

There are 3 inside the box.

SELF-TEST b

1 Find the total.
a

2 Add. b 4+7= c 2+8=
a 6+3= e 9+9= f 5 + = 12

d 4+9=

2.2.1 • Emphasise to the pupils that when adding two quantities, the quantities increase
AB pages 72 - 74 and the value becomes larger.

• Provide more questions in the form of worksheets or question cards.

59

QUICK ADDITION +1 56++11==67
7+1 = 8
0+1=1 9+81+= 11 0= 9

0+0=0 +0 56++00==56 1+1=2
1+ 0 =1 2+1=3
7+0 =7 4 +13=+15= 4
2+3+00==23 8+0=8
4+0=4 9+0=9 0+2=2 +2 5+2=7
1+2=3 6+2=8
1+0 +33== 3 +3 87++22=1=09
5+3=8 2+2=
2+ 3 = 5 3+2=5
3 +43+=36=7 6+3=9 4+2=6 9+2=11
78++33==1110
9+3=12 0+4= +4 65++44==190
7+ 4 = 11
1+4=5 9+84+=413=12
2+3+44==67
4+4=8

2.2.1 • Introduce the basic facts of addition. Guide the pupils to complete the number
sentences.
60
• Carry out a quiz on basic facts and get the pupils to answer spontaneously.
• Discuss the similarities and differences between 3 + 4 = 7 and 4 + 3 = 7.

10++55==65 +5 +6 75+6++666===113112
2+5 =7 5+5=10 0+6=6 98+6+=61=5 14
3 +45+=5 =89 1+6=7
7+56=+152=11
8+95+=513=14 2+ 6 = 8
=9
0

+7 65++77==1123 3+6
87++77==1154 6=1

0 +7=7 +

4

1+7= 8 9+7=16
2+3+77==910
4+7=11
+9
0+9=9 65++99==1154
0+8=8 +8 5+8=13 1+9=10
1+8=9 6+8=14
2+3+88==1101 2+3+99==1112 87++99==1716
78++88==1165 4+9=13 9+9=18
4+8=12 9+8=17

List out the number sentences for the sum of 4.

2.2.1 • Relate the combination of numbers to strengthen pupils’ understanding.
AB pages 75 - 77 • Carry out the activity of saying number sentences that give the same total

amount spontaneously.

61

MY Addition Participants 5 pupils in a group.
PROJECT Maps
Materials Papers and
coloured pens.

Method

1 Create addition maps for the sum of 1 to 18.
For example:

0+3 1+2 Addition map
sum of 3
3

2+1 3+0

2 Decorate the maps.
3 Display your maps.

SELF-TEST
Match.

8+3 7+9 8+8 3+2 4+6

16 11 5 8 10
2+9 1+4 6+2 7+3 0+8

2.2.1 • Guide the pupils to carry out activities to construct addition maps for
the sum of 1 to 18.
62 • Provide more questions in the form of worksheets or question cards.

EASY ADDITION 25
1 Add 25 and 3.

25 + 3 =

Method 1

Count on 3 steps from 25.

25 26 27 28 29 30

Method 2 tens ones Add ones.
2 5
+ 3 5 ones + 3 ones = 8 ones
8

tens ones Add tens.
2 5
+ 0 3 2 tens + 0 tens = 2 tens

2 8



2 5
+ 3
2 8

2.2.2 25 + 3 = 28
AB pages 78 -79
• Guide the pupils to count on in ones from a larger number. Familiarise the pupils
with addition using counters and abacus.

• Guide the pupils to put the digit of ones and tens correctly in the standard written
method.

63

2 Find the total of 17 and 30.
17 + 30 =

Method 1 17 30

Add ones. Add tens
tens ones tens ones
1 7
1 7 + 3 0
+ 3 0 4 7
7

1 7
+ 3 0
4 7

Method 2 Start with 17. Count on
3 steps in tens.

1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20 + 10
21 22 23 24 25 26 27 28 29 30 + 10
31 32 33 34 35 36 37 38 39 40 + 10
41 42 43 44 45 46 47 48 49 50

17 + 30 = 47

2.2.2 • Guide the pupils using 100-square grid to solve addition operation.
• Help the pupils to see the pattern appeared in the 100-square grid. For example,
64 the number on the right side is larger than the number on the left side.

AB page 80

3 Add 2 tens and 6 tens.

Method 1 20 + 60 = Method 2

Count on from the
larger number, 60.

+ 10 + 10 2 0
+ 6 0
60 70 80 8 0

20 + 60 = 80

4 43 + 52 =

Method 1 Method 2 40 50
4 3 43 52
+ 5 2
9 5 32

43 + 52 = 95 40 + 50 = 90
3+ 2= 5

43 + 52 = 95

2.2.2 • Help the pupils to count in tens. Relate it with addition involving multiples of 10.
• Emphasise the correct steps to add using the standard written method.

Use manipulative and concrete materials to enhance the pupils’ understanding.

65

5 How many should be added to 56 to make 79?
56 + = 79

Method 1 Use combination of numbers.

5 6 65
+ 2 3 97
7 9
32

Method 2

Count on in tens from 56 to 76.
Get 20.

41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 90

Then, count in ones
from 76 to 79. Get 3.

20 and 3 is 23.

56 + 23 = 79

2.2.2 • Guide the pupils to add involving an unknown using base ten blocks to enhance their
understanding.
66
AB pages 81 - 82

SHARPEN Use 8 + 2 = 10 to calculate 12 + 8 = .
YOUR Discuss.
MIND

SELF-TEST

1 C o mpl ete these.
a 2 0 b 5 1 c 4 0
+ 8 + 7
+ 3 0


d 2 4 e 8 5 f 3 5
+ 6
+ 6 3 + 1 4 9


2 Show two methods of adding.

a 45 + 3 = b 22 + 70 = c 11 + 36 =

3 Solve these. b 59 + = 89 c 77 + = 99
a 32 + 6 =

2.2.2 • Surf http://math.about.com/od/addingsubtracting/ss/2digaddnr.htm
• Provide more questions in the form of worksheets or question cards.

67

MORE ADDITION
1 Lisa’s sister arranges 8 dolls.

Lisa arranges 3 more dolls.
How many dolls are there
altogether?

8+3=

Method 1 Count all.

1 2 3 4 5 6 7 8 9 10 11

Method 2 9 10 11

I count on from 8.
9, 10, 11.

8 9 10 11

• Guide the pupils to relate addition with counting process learnt in Unit 1.

2.2.2

68

Method 3

8 3

Firstly,
make 10.

8+ 3 =? 10 and 1
21
Then, add
8 + 2 = 10 10 and 1.

10 + 1 = 11
8 + 3 = 11

There are 11 dolls altogether.

2.2.2 • Guide the pupils to understand the method shown. Carry out exercises to make
10 using concrete materials and combination of 10.
• Use i-Think map to visualise the combinations of 10.

69

2 Add 29 and 6. Count on 6 steps
29 + 6 = from 29.

Method 1

29 30 31 32 33 34 35

Method 2

tens ones Add ones.
9 ones + 6 ones = 15 ones
2 9
+ 6 Convert 15 ones to
1 tens and 5 ones.
1 5

tens ones Add tens.

1
2 9
+ 0 6 2 tens + 0 tens + 1 tens

3 5 = 3 tens

1

2 9
+ 6
3 5

2.2.2 29 + 6 = 35

70 • Emphasise that the largest digit in the place value is 9. If it is 10, do regrouping.
• Use manipulative and concrete materials to enhance pupils’ understanding.

AB pages 83 - 84

3 18 + 34 = tens ones Add ones.
Method 1 8 ones + 4 ones = 12 ones
1 8
+ 3 4 Convert 12 ones to 1 tens
1 2 and 2 ones.

tens ones

1 Add tens.
1 8
+ 3 4 1 tens + 3 tens + 1 tens
5 2 = 5 tens

1

1 8
+ 3 4
5 2

Method 2
18 + 34 =
2 32

2.2.2 20 + 32 = 52

18 + 34 = 52

• Guide the pupils to add by regrouping using tens complement and 100-square grid
such as in page 66.

• Surf http://www.softschools.com/math/addition/2_digit_addition/2_digit_addition_
with_regrouping/

71

4 39 + 47 = Method 2 39 47
Method 1

30 9 40 7

1 Add tens:
30 + 40 = 70
3 9 Add ones:
+ 4 7 9 + 7 = 16
8 6

7 0
+ 1 6
8 6

39 + 47 = 86

5 What number should be added to 58 to make 63?

58 + = 63 Count on from
58 to 63.

Get 5 steps.

58 59 60 61 62 63

58 + 5 = 63

2.2.2 • Guide the pupils to add using the standard written method. Emphasise the steps on
adding correctly.
72
AB pages 85 - 87

SHARPEN Which 15 15
YOUR answer +9 +9
MIND is correct?
Why? 114 24

SELF-TEST

1 Complete these.

a 8 6 b 4 7 c 5 1
+ 2 9
+ 5 + 3 8

f 4 + 8 =

d 9 + 6 = e 5 + 7 =
1 2

2 Add. b 54 + 19 = c 32 + 68 =
a 66 + 8 =

d = 26 + 74 e + 9 = 16 f 17 + = 84

2.2.2 • Guide the pupils to write addition operation in the standard written method correctly.
• Discuss the mistakes that will occur when pupils do not write and add correctly.
• Provide more questions in the form of worksheets or question cards.

73

RECOGNISE SUBTRACTION

1

There are
6 balls. Nik
takes out

2 balls.

a How many balls are left? 6

Take away 2 from 6. 4 2
4 left.

There are 4 balls left.

b Count the difference of red loops and blue loops.

Red loops are 2 more.
Blue loops are 2 less.

5
2 The difference of 5 and 3 is 2.

3

The difference of red loops and blue loops is 2.

• Guide the pupils to understand the concept of subtraction by applying

2.1.1 simulation and using vocabulary related to the concept of subtraction.
• Explain that difference is the values between two groups.

74

2 3 from 12 sandwiches

are sold.

a Calculate the balance of the sandwiches.
12 less 3 is 9.

12 minus 3 is equal to 9.

12 – 3 = 9 Number sentence

minus – = is equal to

The balance of the sandwiches is 9.

b What is the difference in numbers between

and ?
The difference of 9and 7 is 2.
9 minus 7 is equal to 2.

9–7=2

The difference in numbers between and is 2.

2.1.1 • Emphasise the meaning of symbols for “subtraction” and “is equal to”.
2.1.2 • Carry out an activity using concrete materials and relate it to our daily life to
2.1.3
enhance pupils’ understanding.
AB pages 88 -91 • Explain that balance is the value left when the original value is reduced.

75

3 Dina’s mother buys 6 . She gives 4 to her
nieces. Find the balance of ?

6–4=

Count back 4 steps from 6.

1 23456

6–4= 2 is 2.
The balance of

4

How many are not broken?
Method 2
8–3=
Method 1

3
8

5

8–3= 5

5 are not broken.

2.3.1 • Guide the pupils to carry out simulations and use representations to enhance their
subtraction skills.
76
• Relate pupils’ understanding in addition with subtraction.

5 What is the difference in numbers between and ?

11 – 4 =

0 1 2 3 4 5 6 7 8 9 10 11
11 – 4 = 7

The difference in numbers between and is 7.
6

12 pieces 5 pieces

How many tarts has Mary taken out?

12 – = 5

1 2 3 4 5 6 7 8 9 10 11 12

12 – 7 = 5
Mary has taken out 7 tarts.

2.3.1 • Guide the pupils to solve the problems involving unknown using various methods
AB pages 92 - 93 that are suitable.

• Guide the pupils to use combination of numbers to solve subtraction.

77

Complete these.

SHARPEN a 8– =7 b – =6
YOUR
MIND =– –=

04 8

=–= =–=

– =5 – 1=6

SELF-TEST
1 How many are left?

2 Find the difference in number of –=
and .

–=

3 Solve these. b 10 – 8 = c 14 – 7 =
a 9–2= e = 17 – 9 f 13 – = 8

d = 15 – 6

2.3.1 • Surf https://www.superteacherworksheets.com/subtraction-basic.html
• Provide more questions in the form of worksheets or question cards.
78

MY Knowing me
PROJECT

Talk about yourself.
Method
Write the number sentences of addition or subtraction.
The answers are related to yourself.

Examples: 1 Date of birth: 8. Write 6 + 2 = 8.
2 Age: 7 years old. Write 10 – 3 = 7.

Date of birth Age
6+2=8 10 – 3 = 7

Month of birth Shoe size

Mother’s age Father’s age

Number of sisters Number of brothers

2.2 • Adapt the information as needed while carrying out the activity.
2.3 • Ask the pupils to exchange information among themselves.

2.5
2.6

79

QUICK SUBTRACTION

–3 –0 –1 –2
3 – 3 = 0 0 – 0 = 0 1 – 1 = 0 2 – 2 = 0
1 – 0 = 1 3 – 2 = 1
2 – 0 = 2 3 – 1 = 2
3 – 0 = 3 4 – 1 = 3 5 – 2 = 3
4 – 0 = 4 5 – 1 = 4 6 – 2 = 4
5 – 0 = 5 6 – 1 = 5
7 – 1 = 6 8 – 2 = 6
7 – 0 = 7 8 – 1 = 7 9 – 2 = 7
8 – 0 = 8 10 – 2 = 8
10 – 1 = 9 11 – 2 = 9

5 – 3 = 2 –4 –5 –6
6 – 3 = 3 4 – 4 = 0 6 – 6 = 0
5 – 4 = 1 6 – 5 = 1 7 – 6 = 1
7 – 3 = 4 6 – 4 = 2 7 – 5 = 2 8 – 6 = 2
8 – 3 = 5 8 – 5 = 3 9 – 6 = 3
8 – 4 = 4 9 – 5 = 4
9 – 3 = 6 9 – 4 = 5 10 – 5 = 5 11 – 6 = 5
10 – 3 = 7 10 – 4 = 6 11 – 5 = 6
11 – 3 = 8 12 – 5 = 7 13 – 6 = 7
12 – 4 = 8 14 – 6 = 8
13 – 4 = 9 14 – 5 = 9 15 – 6 = 9

2.3.1 • Guide the pupils to use concrete materials and flash cards to strengthen their
understanding.
8800

–7 –8 –9
7 – 7 = 0 8 – 8 = 0 9 – 9 = 0
8 – 7 = 1 9 – 8 = 1 10 – 9 = 1
9 – 7 = 2 10 – 8 = 2
11 – 8 = 3 12 – 9 = 3
11 – 7 = 4 13 – 9 = 4
13 – 8 = 5 14 – 9 = 5
13 – 7 = 6 15 – 9 = 6
14 – 7 = 7 15 – 8 = 7 16 – 9 = 7
15 – 7 = 8 16 – 8 = 8
16 – 7 = 9 17 – 8 = 9 18 – 9 = 9

SELF-TEST Try to complete these
subtraction tables.

1 Select question cards for the answer in .

a2 b5
2–0 4–1 8–3 6–1

10 – 4 5 – 3 10 – 8 7 – 2 5 – 4 12 – 7
8 – 6 12 – 9 15 – 9 10 – 5

2 Write the numbers in the boxes. Create the correct
number sentences.

a 437 b 11 5 6 c 9 17 8

–= –= –=
–= –= –=

22..33..11 • Help the pupils to understand the basic facts of subtraction and using it.
AB pages 94 - 96 Ask them to look at the pattern of basic facts of subtraction and relate it
to the basic facts of addition.
• Provide more questions in the form of worksheets or question cards.

81

EASY SUBTRACTION

1 There are 19 Seri Ayu cakes on the
tray. Mother takes out 5 cakes.
Calculate the number of cakes left
on the tray.

19 – 5 =
Method 1

Count back 5 steps from 19.

10 11 12 13 14 15 16 17 18 19

Method 2
1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20

Start at 19. Move 5 steps
to the left. 18, 17, 16, 15, 14.

19 – 5 = 14
The number of cakes left is 14.

2.3.2 • Guide the pupils to count back from a larger number. Familiarise them to subtract
using 100-square grid. Guide the pupils to look at the number pattern on the
82 100-square grid.

2 I read 20 from 60 pages. How many

pages are left for me to finish?

Subtract 20 from 60.
60 – 20 =

Method 1 Count back in
20 30 40 50 60 tens from 60.

– 10 – 10

Method 2 tens ones

6 0 Subtract ones.
– 2 0
0 0 ones – 0 ones = 0 ones

tens ones

6 0 Subtract tens.
– 2 0
4 0 6 tens – 2 tens = 4 tens



6 0
– 2 0
4 0

60 – 20 = 40
There are 40 pages left.

2.3.2 • Help the pupils to recall the method of counting in tens. Relate it with addition
involving counting in tens. Use concrete materials to assist them.

83

3 What is the difference in numbers
between the green and blue buttons?
37
Method 1 14 37 – 14 =

Match 10 and 4. There are
23 more green buttons.

Method 2 Subtract ones.
7 ones – 4 ones = 3 ones
tens ones

3 7
– 1 4
3

tens ones Subtract tens.
3 tens – 1 tens = 2 tens
3 7
– 1 4
2 3



3 7
–1 4
2 3

37 – 14 = 23

The difference in numbers between
the green and blue buttons is 23.

2.3.2 • Guide the pupils to subtract using the standard written method. Emphasise to
them about the correct steps to do subtraction.
84 • Explain the method of finding differences using concrete materials such as base ten

blocks, counters and others.

4 How much less is 28 from 59?
59 – 28 =

Method 1

Subtract ones. Subtract tens.

tens ones tens ones

5 9 5 9

– 2 8 – 2 8
1 3 1

5 9
– 2 8
3 1

Method 2 S ubtract tens: 50 – 20 = 30
59 – 28 = ?
Subtract ones: 9 – 8 = 1
50 9 20 8 Answer: 30 + 1 = 31

59 – 28 = 31

2.3.2 • Guide the pupils to subtract using standard written method.
• Encourage the pupils to calculate quickly.

85

5 How many should be subtracted from 86 to make 53?
86 – = 53

Method 1

41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 90

Count back in tens Then, count in ones
from 86 to 56. from 56 to 53. Get 3.
Get 30. 30 and 3 make 33.

Method 2 8 6
8 6 35 33
– 3 3
5 3

86 – 33 = 53

2.3.2 • Guide the pupils to solve the problems involving unknown using 100-square grid and
combination of numbers.
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• Help them to see the pattern in the 100-square grid such as pattern in tens to help
them doing quick calculation.

AB pages 97 - 101

SHARPEN Form subtraction number sentences using
YOUR the given numbers. Each number can be
MIND used more than once.

234568 9

List out the number sentences.

SELF-TEST

1 Complete these.

a 5 7 b 6 8 c 4 5
– 6 – 5
– 3 0


d 3 1 e f
– 2 0 8 9 7 9
– 6 2 – 4 3


2 Solve these.

a 26 – 3 = b = 55 – 14 c 97 – = 62

2.3.2 • Guide the pupils to write subtraction number sentences without regrouping in the
Sharpen Your Mind activity.

• Provide more questions in the form of worksheets or question cards.

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MORE SUBTRACTION

1 Akid has 15 tops.
He gives 8 tops to Amar.
How many tops does Akid have now?

15 – 8 =

Method 1 Take away 8
from 15. 7 left.

Method 2 15 – 8 = ? 15 = 10 + 5
5 10

2.3.2 10 – 8 = 2

2+ 5 =7
15 – 8 = 7

Akid has 7 tops now.

• Carry out exercises on finding combination of two-digit numbers in tens and ones.
• Surf https://www.education.com/worksheet/article/practice-subtraction-monkey/

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2 Subtract 7 from 63.
63 – 7 =

Method 1

Convert 1 tens to 10 ones.

10 ones + 3 ones = 13 ones

tens ones Subtract ones.

56 133
– 7 13 ones – 7 ones = 6 ones
6

tens ones Subtract tens.
5 tens – 0 tens = 5 tens
56 133
– 0 7
5 6

5 13

6 3
– 7
5 6

Method 2 Add 3 and 7 to make 10.
Add 3 to 63 too.
63 – 7 = ?

+3 +3

66 – 10 = 56

63 – 7 = 56

2.3.2 • Guide the pupils to subtract by regrouping using counters.
AB pages 102 - 103 • Emphasise to the pupils to write the digits in the correct place values.

89

3 50 – 24 =
Method 1

Convert 1 tens to 10 ones.
0 ones + 10 ones = 10 ones

Subtract ones. Subtract tens.

tens ones tens ones

45 100 45 100
– 2 4 – 2 4
6 2 6

4 10

5 0
– 2 4
2 6

Method 2

Count back in tens.
Then, in ones.

11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50

50 – 24 = 26

2.3.2 • Guide the pupils to write subtraction operation in the standard written method
correctly.

• Guide the pupils to subtract using 100-square grid.

90

4 Calculate the difference of 28 and 42.
42 – 28 =

Method 1 tens ones 34 122
– 2 8
tens ones 34 122 1 4
– 2 8
34 122 1 4
– 2 8
4

Method 2

I am using the combination of numbers.

42 28

30 12 20 8

Subtract: 30 – 20 = 10
12 – 8 = 4
Answer: 10 + 4 = 14

42 – 28 = 14

• Guide the pupils to do quick calculation using combination of numbers.

2.3.2

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5 31 – = 25
Method 1

23 24 25 26 27 28 29 30 31 32 33

Method 2 11 is 5 and 6.

2 11 11 5
6
3 1
– 6
2 5

31 – 6 = 25

SELF-TEST

1 Calculate the balance.

a 2 3 b 5 2 c 3 1 d 6 0

– 6 – 7 – 1 9 – 4 4



2 Solve these. b 61 – 5 = c 34 – 15 =
a 12 – 8 =

d 95 – 88 = e = 40 – 28 f 26 – = 17

2.3.2 • Surf https://www.ixl.com/math/grade-1
• Provide more questions in the form of worksheets or question cards.
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AB pages 104 - 106

ADDITION AND SUBTRACTION STORIES

1
There are 5 .

There are 3 .

There are 8 toy cars

altogether.

2

There are 8 flowered hair
clips and ribboned
hair clips. The total number
of hair clips is .

3

Mila has purple stickers.
Mei Li has red stickers.
Their total number
of stickers is .

2.4.1 • Guide the pupils to create stories using their own words. Carry out the activity in
pairs; one pupil shows a picture card and the other tells the story.

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