Subtraction of 2 Digit Numbers With Remaining (Primary 2)

MATHEMATICS

SECOND TERM  

WEEK 3

PRIMARY 2

THEME – BASIC OPERATIONS 

PREVIOUS LESSON – Second Term Scheme of Work and Plan Lesson Notes for MATHEMATICS Week 1 to Week 12 Primary Schools

TOPIC – SUBTRACTION OF 2 DIGIT NUMBERS WITHOUT REMAINING 

PERFORMANCE OBJECTIVES 

By the end of the lesson, the pupils should have attained the following objectives (cognitive, affective and psychomotor) and should be able to –

1. subtract two 2-digit numbers without renaming.

2. solve word problems involving subtraction of whole numbers.

ENTRY BEHAVIOUR

Subtraction of Numbers or objects

INSTRUCTIONAL MATERIALS

The teacher will teach the lesson with the aid of:

1. Number cards

2. Cardboard strips with numerals and number line, etc.

3. Number beads

4. Sticks

5. Counters such as: oranges, beans seeds, bottle tops.

METHOD OF TEACHING – Choose a suitable and appropriate methods for the lessons.

Note – Irrespective of choosing methods of teaching, always introduce an activities that will arouse pupil’s interest or lead them to the lessons. 

REFERENCE MATERIALS

1. Scheme of Work

2. 9 – Years Basic Education Curriculum

3. Course Book

4. All Relevant Material

5. Online Information

CONTENT OF THE LESSON  

LESSON ONE – INTRODUCTION 

Pupil’s Activities – Subtraction of 1 Digit Numbers 

Introductory Questions

9 – 6 =

8 – 7 =

5 – 3 =

8

– 5

_______

Teacher’s remark – Subtraction means take – away or remove.

Pupil’s Activities 2 – Expansion of Numbers 

Samples

10 = 10 + 0

1 Ten + 0 Unit

 

12 = 10 + 1

1 Ten + 1 Unit

 

21 = 20 + 1

2 Tens + 1 Unit

 

36 = 30 + 6

3 Tens + 6 Units

Expand

1. 15 = ____ + ____

____ Ten + ____ Units

 

2. 34 = ____ + ____

____ Tens + ____ Units

 

3. 19 = ____ + ____

____ Tens + ____ Units

 

4. 39 = ____ + ____

____ Tens + ____ Units

Teacher’s/Pupil’s Activities 3 – Subtraction of 2 Digit Numbers Without Renaming

Working Examples

1. 58 – 36

58 = 50 + 8 = 5 Tens + 8 Units

– 36 = 30 + 6 = 3 Tens + 6 Units

_______________________________

22 = 20 + 2 = 2 Tens + 2 Units

2. 63 – 33

63 = 60 + 3 = 6 Tens + 3 Units

– 33 = 30 + 3 = 3 Tens + 3 Units

_______________________________

30 = 30 + 0 = 3 Tens + 0 Units

Pupil’s Activities 4 – Exercise/Take Home 

1. 32 – 11

2. 49 – 16

3. 75 – 41

4. 76 – 67

LESSON TWO – USING VERTICAL/COLUMN METHOD

Pupil’s Activities 1 – Arrange the Numbers under Tens and Units

Quantitative Reasoning,

Sample

23 = 20 + 3 = Tens + Units

T U

2 3

 

37 = 30 + 7 = Tens + Units

T U

3 7

Teacher’s/Pupil’s Activities 2 – Arrange the Numbers under Tens and Units for Easy Subtraction 

Working Examples

1. 22 – 11

T U

// 2 2 //

+   / 1 1  /

________

1 1

 

2. 11 + 26

T U

// 2 6 //////

+ / 1 4 ////

_________

1 2

Pupil’s Activities 3 – Exercise/Take Home

Copy and complete the following using the vertical/column method.

1. 79 – 22

2. 25 – 13

3. 18 – 11

4. 16 – 13

LESSON THREE – SUBTRACTION of 2 – DIGIT NUMBERS WITH RENAMING 

 Teacher’s/Pupil’s Activities 1 – Regrouping Numbers 

Sample

52 = 50 + 2

= 40 + 10 + 2

= 40 + 12

35 = 20 + 15

Regroup

21

64

Teacher’s/Pupil’s Activities 2 – Regrouping Subtraction 

Working Examples

61 – 15

61 = 50 + 11

– 15 = 10 + 5

_______________

46 = 40 + 6

74 — 67

74 = 60 + 14

— 67 = 60 + 7

_________________

7 = 00 + 7

Pupil’s Activities 3 – Exercise/Take Home 

1. 60 — 35

2. 78 — 59

3. 25 — 17

4. 81 — 39

LESSON FOUR – ARRANGE THE NUMBERS UNDER TENSE AND UNITS FOR EASY SUBTRACTION 

Pupil’s Activities 1 – Arrange the Numbers under Tens and Units

Quantitative Reasoning,

Sample

23 = 20 + 3 = Tens + Units

T U

2 3

 

37 = 30 + 7 = Tens + Units

T U

3 7

 

Teacher’s/Pupil’s Activities 2 – Arrange the Numbers under Tens and Units for Easy Subtraction 

Working Examples

1. 20 – 11

T U

²3 ¹4

— 1 5

________

1 9

 

2. 56 – 47

T U

³4 ¹6

—  1 7

_________

2 9

 

Pupil’s Activities 3 – Exercise/Take Home

Copy and complete the following using the vertical/column method.

1. 70 – 22

2. 22 – 13

3. 20 – 11

4. 66 – 37

PRESENTATION

To deliver the lesson, the teacher adopts the following steps:

1. To introduce the lesson, the teacher revises the previous lesson. Based on this, he/she asks the pupils some questions;

2. Revises subtraction of 1-digit numbers.

Pupil’s Activities – Solve quick problems on subtraction of 1-digit numbers.

3. Leads pupils to identify number of tens and write in 2-digit numbers i.e. place value.

Practice expressing place values e.g. 36 = 3 tens, 6 units and 28 = 2 tens, 8 units.

4. Guides pupils in the use of counters to demonstrate subtraction as taking away in 2-digit numbers.

Give the answer to given problem using counter e.g. Counts 44 and take away 12. That’s 44 – 12 = 32

5. Guides pupils to identify the digits that are in tens and units e.g.

43 = 4 tens + 3 units

57 = 5 tens + 7 units

83 = 8 tens + 3 units

Pupil’s Activities – Mention the digits in the tens and units in the expanded form.

5. Leads pupils to give examples of everyday activities where accuracy of addition and subtraction are required.

Pupil’s Activities – Gives examples of everyday activities where accuracy of addition and subtraction are required.

6. Guides pupils in solving subtraction problems on the board.

Pupil’s Activities – Subtract given 2-digit numbers.

7. Guides pupils to mention the number of tens and units in a given e.g. Subtract 47 from 54, rename 54 = 40 + 14; then subtract.

Pupil’s Activities – Mention the numbers of tens and units in a given number.

CONCLUSION

To conclude the lesson for the week, the teacher revises the entire lesson and links it to the following week’s lesson.

LESSON EVALUATION 

Pupils to:

1. subtract 2-digit numbers without exchanging or renaming.

2. mention 4 everyday activities where accuracy is needed.