Second Term Lesson Note for Week Three
Class : Primary Two
Subject : Mathematics
Topic : Subtraction of 2 digit number with regrouping (borrowing)
Duration : 80 Minutes
Period : Double Periods
Reference Book :
- New Method Mathematics for Primary Schools, Book 2, by Learn Africa.
- Lagos State Unified schemes of work for lower Primary, Primary 1 – 3.
- Online Resources
Instructional Material : Chart showing the subtraction of Numbers
Previous Knowledge : Learners are familiar with subtraction of Numbers only.
Learning Objectives : By the end of the lesson learners will be able to :
i. Explain the term “Subtraction”
ii. Solve problems on Subtraction of Numbers with borrowing or regrouping.
Content :
Subtraction means take away, minus, difference, reduce, less, etc.
The sign of minus is ( – ).
When Subtracting 2 digit numbers from each other, we can either apply the
I. Short method ( Direct method) or
II. Expanded form method
Short or Direct Method.
You start your subtraction from the Unit, which is your right hand side.
If the number at the top is less than the number at the bottom, we borrow one (1) from tens.
Then perform the subtraction or take away from the Unit side before the tens side.
| T U | T U | T U |
| ¹ 2 ¹4 | ⁴ 5 ¹3 | 6 ¹5 |
| – 1 8 | – 1 9 | – 4 7 |
| 0 6 | 3 4 | 1 8 |
Subtraction of Numbers using Expanded Method :
When performing subtraction of numbers using expanded form method, we first expand or split the number into tens and unit. That is 24 = 20 + 4 and 18 = 10 + 8.
Then, consider the unit side, 4 cannot take away 8. So we regroup by borrowing 10 from the 20
| T U | Expand | |
| 2 4 | 20 + 4 | 10 + (14) |
| – 1 8 | 10 + 8 | 10 + 8 |
| 0 + 6 |
Presentation Steps :
Step 1 : Revision of the previous week topic with the learners by asking them questions orally. He/ she calls them to the board to express themselves and makes correction.
Step 2 : He / she introduces the new topic by explaining the meaning of subtraction and words synonymous to take away.
Step 3 : Explain the expanded form methods on subtraction
Step 4 : The teacher then describe the shortened or direct method
Evaluation :
Solve the following using expanded form:
T U T U 4 6 6 7
– 2 9 – 3 8
CONCLUSION : The teacher summarizes the lesson again for a better understanding and correct them as he/ she moves round in the class.