Class: Primary 1
Term: 1st Term
Week: 6
Age: 6 years
Duration: 45 minutes
Subject: Mathematics
Curriculum Theme: Number and Numeration
Previous Lesson: Addition, Adding 2-Digit Numbers.
Topic: Subtraction
Subject Matter: Subtraction of whole numbers lesser than 100 without “carrying over” and its real-life applications.

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

Define subtraction as taking away.
Arrange two-digit numbers in Tens and Units columns.
Carry out subtraction operations for whole numbers less than 100 without “carrying over”.
Give examples of everyday situations where accuracy in subtraction is needed.

Affective Domain:

Appreciate the importance of accuracy in subtraction.
Show carefulness when arranging numbers and performing subtraction.

Psychomotor Domain:

Correctly solve subtraction problems such as 95 – 25 and 67 – 50.
Neatly write and arrange numbers in Tens and Units columns.

Discuss and share ideas on where subtraction is used in daily life.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Primary 1 Mathematics.
State Unified Scheme of Work for Primary 1 Mathematics.
New Oxford Primary Mathematics for Nigeria, Book 1.
https://nigerianinfopedia.com.ng/how-to-teach-subtraction-to-primary-school-children/
https://www.study.com/academy/lesson/subtraction-lesson-for-kids-definition-facts.html

Instructional Materials

The teacher will teach this lesson with the aid of:

Whiteboard and markers
Number charts
Counters (e.g., bottle caps, stones, sticks)
Flashcards with simple subtraction problems
Real-life objects for demonstration (e.g., fruits, pencils)

Rationale for the Lesson

This lesson helps pupils understand the basic concept of taking away, which is fundamental to daily numerical activities. It enables them to solve simple real-life problems involving subtraction, building a strong foundation for more complex mathematical operations.

Prerequisite/Previous Knowledge

Pupils can count numbers up to 100, identify digits, and understand the concept of Tens and Units.

Lesson Content/Board Summary

Subtraction of Whole Numbers Less Than 100 (Without Carrying Over)

What is Subtraction?

Subtraction means taking away a smaller number from a larger number. It tells us how many are left or the difference between two numbers. The symbol for subtraction is ‘–’ (minus).

Arranging Numbers in Tens and Units (T U)

When we subtract two-digit numbers, it is important to arrange them correctly in columns. The ‘T’ stands for Tens, and the ‘U’ stands for Units. We always subtract the Units first, then the Tens.

How to Subtract Without Carrying Over

Arrange the numbers vertically, ensuring the Units digits are under each other and the Tens digits are under each other.
Start subtracting from the Units column (right side).
Then, subtract the numbers in the Tens column (left side).

Worked Examples:

Example 1: Subtract 25 from 95

T U

9 5

– 2 5

—–

Step 1: Subtract the Units: 5 – 5 = 0. Write 0 under the Units column.

Step 2: Subtract the Tens: 9 – 2 = 7. Write 7 under the Tens column.

Answer: 70

Example 2: Subtract 50 from 67

T U

6 7

– 5 0

—–

Step 1: Subtract the Units: 7 – 0 = 7. Write 7 under the Units column.

Step 2: Subtract the Tens: 6 – 5 = 1. Write 1 under the Tens column.

Answer: 17

Everyday Situations Needing Accurate Subtraction:

The following are situations where accurate subtraction is needed:

Calculating change when buying items.
Finding out how many items are left after some have been used or sold.
Determining the difference in age between two people.
Counting how many days are left until an event.
Sharing items among friends and knowing how many are left.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Lesson: Subtraction of Whole Numbers

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils and asks them to count some objects (e.g., 10 pencils). The teacher then takes away 3 pencils and asks how many are left, leading to the concept of subtraction.
Pupils’ Activity: Pupils respond to greetings, count the objects, and try to guess how many are left.
Learning Point: Pupils are introduced to the idea of “taking away” and the lesson topic.

Step 2: Explanation of Subtraction

Time: 7 minutes
Teaching Skill: Explanation/Demonstration
Teacher’s Activity: The teacher defines subtraction using simple terms and demonstrates with counters (e.g., “If I have 8 bottle caps and I take away 3, how many are left?”). The teacher introduces the minus sign (-).
Pupils’ Activity: Pupils listen attentively, observe the demonstration, and participate by counting and answering questions.
Learning Point: Pupils understand the meaning of subtraction and its symbol.

Step 3: Arrangement in Tens and Units

Time: 8 minutes
Teaching Skill: Demonstration/Guidance
Teacher’s Activity: The teacher explains the importance of arranging numbers in Tens (T) and Units (U) columns before subtracting. The teacher writes a two-digit number (e.g., 47) on the board and shows how to place 4 in the Tens column and 7 in the Units column.
Pupils’ Activity: Pupils observe carefully and practice arranging numbers on their slate or in their exercise books as guided by the teacher.
Learning Point: Pupils learn how to correctly arrange numbers for subtraction in T U format.

Step 4: Guided Practice (Example 1)

Time: 7 minutes
Teaching Skill: Guided Practice
Teacher’s Activity: The teacher writes the first example (95 – 25) on the board, arranges it in T U columns, and guides pupils through the step-by-step subtraction process, starting from the Units column.
Pupils’ Activity: Pupils follow the teacher’s steps, performing the subtraction in their books and stating the answers for each column.
Learning Point: Pupils practice performing subtraction without “carrying over” with guidance.

Step 5: Guided Practice (Example 2)

Time: 6 minutes
Teaching Skill: Guided Practice
Teacher’s Activity: The teacher presents another example (67 – 50) and guides pupils through solving it, encouraging them to work more independently but still providing support.
Pupils’ Activity: Pupils solve the problem in their books, applying the steps learned, and share their answers.
Learning Point: Pupils reinforce their understanding and skill in subtraction.

Step 6: Real-life Applications

Time: 5 minutes
Teaching Skill: Discussion/Application
Teacher’s Activity: The teacher asks pupils to think of situations in their daily lives where they might need to use subtraction, prompting them with examples like buying things and getting change.
Pupils’ Activity: Pupils mention various situations from their experiences where subtraction is used.
Learning Point: Pupils connect subtraction to real-world scenarios and understand its practical importance.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

What does subtraction mean?
Arrange 84 – 31 in Tens and Units columns.
Solve: 78 – 25 = ?
Mention two places where you use subtraction in your daily life.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 2 minutes
Teaching Skill: Summarization
Teacher’s Activity: The teacher summarizes the lesson by reminding pupils that subtraction means taking away and that it is important to arrange numbers correctly in T U columns. The teacher assigns homework: solve 59 – 13 and 46 – 20.
Pupils’ Activity: Pupils listen to the summary and copy down the homework.
Learning Point: Pupils consolidate their learning and are given tasks to practice at home.

Home Task: Solve two new exercises on Subtraction. Show each step and check each answer.

Lesson Keywords

Subtraction – Taking away a number from another number.
Minus (-) – The symbol for subtraction.
Tens (T) – The column for the digit representing groups of ten.
Units (U) – The column for the digit representing single items.
Difference – The result of subtracting one number from another.

Differentiation

For pupils who grasp the concept quickly, the teacher can provide additional challenge problems with slightly larger numbers (still without carrying over). For those needing more support, the teacher will provide extra counters and one-on-one guidance, breaking down the steps further.

Note for teachers using this lesson plan

Ensure that pupils have a solid understanding of place value (Tens and Units) before introducing subtraction. Use plenty of visual aids and hands-on activities with counters to make the concept concrete. Emphasize starting subtraction from the Units column. Encourage pupils to explain their steps to reinforce their understanding.