Class: Primary 4
Term: 1st Term
Week: 7
Age: 9 years
Duration: 45 minutes
Subject: General Mathematics
Curriculum Theme: Number and Numeration
Previous Lesson: Fraction, Equivalent Fractions, Ordering and Sharing Applications.
Topic: ADDITION OF WHOLE NUMBERS
Subject Matter: Addition of whole numbers up to hundreds of thousands with and without remainder, using abacus for addition, importance of place value in addition, quantitative reasoning on missing numbers in addition tables.

Specific Objectives

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

Cognitive Domain:

Define addition of whole numbers.
Explain the importance of place value in addition.
Solve addition problems of whole numbers up to hundreds of thousands, with and without remainder.
Solve quantitative reasoning problems involving missing numbers in addition tables.

Affective Domain:

Appreciate the importance of place value for correct addition.
Develop carefulness and accuracy when adding numbers.

Psychomotor Domain:

Use an abacus to perform addition of whole numbers.
Correctly arrange digits according to their place values during addition.

Work with peers to solve addition problems.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Primary 4 Mathematics.
State Unified Scheme of Work for Primary 4 Mathematics.
New General Mathematics for Primary Schools, Book 4.

Instructional Materials

The teacher will teach this lesson with the aid of:

Textbook
Abacus
Place value chart
Flashcards with addition problems

Rationale for the Lesson

This lesson helps pupils to understand a fundamental mathematical operation used daily. It enables them to perform calculations accurately, which is important for managing money, shopping, and solving everyday problems involving quantities. Understanding place value ensures that addition results are always correct.

Prerequisite/Previous Knowledge

Pupils can identify and write whole numbers up to thousands. They also understand basic counting and the concept of place value for smaller numbers.

Lesson Content/Board Summary

ADDITION OF WHOLE NUMBERS

Definition of Addition

Addition is the process of combining two or more numbers (addends) to find their total sum.

Importance of Place Value in Addition

Place value is important in addition because:

It ensures that digits of the same place value (units, tens, hundreds, thousands, etc.) are aligned correctly before adding.
It prevents errors in calculation, especially when dealing with larger numbers.
It makes the process of carrying over (when the sum of a column is 10 or more) easier and more accurate.

Addition Using an Abacus

An abacus is a tool used for calculations. Each rod on an abacus represents a specific place value (e.g., units, tens, hundreds). To add using an abacus:

Represent the first number by moving beads on the rods.
Then, add the second number by moving more beads, starting from the units rod.
When a rod has 10 beads, remove them and move one bead to the next rod (carrying over).

Addition of Whole Numbers (Up to Hundreds of Thousands)

This involves adding numbers with up to six digits. The process is similar whether there is a remainder (carrying over) or not.

The following are steps for adding whole numbers:

Arrange the numbers vertically, aligning digits according to their place values (units under units, tens under tens, etc.).
Start adding from the units column.
If the sum of a column is less than 10, write the sum below the line in that column.
If the sum is 10 or more, write the unit digit of the sum below the line and carry over the tens digit to the next column on the left.
Continue this process for all columns until all digits have been added.

Example 1 (Without Remainder):

  23456
+ 14321
-------
  37777

Example 2 (With Remainder):

  58792
+ 34567
-------
  93359

Quantitative Reasoning on Missing Numbers in Addition

Quantitative reasoning problems in addition require pupils to find missing digits or numbers in an addition sum by applying their understanding of addition and place value.

The following is an example:

Fill in the missing numbers:

  _ 4 5
+ 1 2 _
-------
  3 _ 8

Solution:

For the units column: 5 + ? = 8. So, the missing number is 3.
For the tens column: 4 + 2 = ?. So, the missing number is 6.
For the hundreds column: ? + 1 = 3. So, the missing number is 2.

  2 4 5
+ 1 2 3
-------
  3 6 8

Teaching Methods/Instructional Techniques

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

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils and asks them to count some items in the classroom, like the number of desks and chairs. The teacher then asks how they would find the total number of desks and chairs combined. This leads to the concept of addition.
Pupils’ Activity: Pupils respond to the teacher’s questions and participate in counting. They suggest ways to find the total.
Learning Point: Pupils are introduced to the concept of combining numbers (addition).

Step 2: Definition of Addition and Importance of Place Value

Time: 8 minutes
Teaching Skill: Explanation/Discussion
Teacher’s Activity: The teacher defines addition and explains why place value is very important when arranging numbers for addition, using a place value chart to demonstrate alignment.
Pupils’ Activity: Pupils listen, take notes, and ask questions for clarification. They observe the place value chart.
Learning Point: Pupils understand what addition is and why place value is important for accurate sums.

Step 3: Demonstration of Addition using Abacus

Time: 8 minutes
Teaching Skill: Demonstration
Teacher’s Activity: The teacher demonstrates how to use an abacus to add two small whole numbers, showing how beads are moved and how carrying over works. Pupils are guided to try it themselves.
Pupils’ Activity: Pupils observe the demonstration, ask questions, and practice using the abacus if available.
Learning Point: Pupils learn a practical method for performing addition using an abacus.

Step 4: Addition of Whole Numbers (Without Remainder)

Time: 7 minutes
Teaching Skill: Guided Practice
Teacher’s Activity: The teacher writes examples of addition problems without remainder on the board, guiding pupils through the steps of arranging numbers and adding column by column.
Pupils’ Activity: Pupils copy the examples and solve similar problems provided by the teacher in their notebooks.
Learning Point: Pupils learn to add whole numbers without carrying over.

Step 5: Addition of Whole Numbers (With Remainder)

Time: 7 minutes
Teaching Skill: Explanation/Practice
Teacher’s Activity: The teacher introduces addition problems with remainder (carrying over). The teacher explains and demonstrates clearly how to carry over digits to the next column.
Pupils’ Activity: Pupils pay close attention to the carrying-over process and practice solving problems with remainders.
Learning Point: Pupils learn to add whole numbers involving carrying over.

Step 6: Quantitative Reasoning

Time: 5 minutes
Teaching Skill: Problem Solving
Teacher’s Activity: The teacher presents simple quantitative reasoning problems involving missing numbers in addition tables, guiding pupils on how to deduce the missing digits.
Pupils’ Activity: Pupils attempt to solve the quantitative reasoning problems and explain their reasoning.
Learning Point: Pupils apply addition skills to solve problems with missing numbers.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

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

Define addition of whole numbers.
State two reasons why place value is important when adding numbers.
Add 35,123 and 21,456.
Add 47,859 and 23,478.
Fill in the missing numbers:
```
  4 _
+ _ 3
-----
  7 9
```

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 1 minute
Teaching Skill: Summarization
Teacher’s Activity: The teacher summarizes the main points of the lesson, emphasizing the importance of accurate addition in daily life and assigns homework from the textbook.
Pupils’ Activity: Pupils listen and copy down the homework.
Learning Point: Pupils recall the key concepts of the lesson and prepare for further practice.

Home Task: Solve three new exercises on ADDITION OF WHOLE NUMBERS. Show each step and check each answer.

Lesson Keywords

Addition – The process of combining two or more numbers to find their total sum.
Sum – The result obtained from adding two or more numbers.
Whole Numbers – Numbers without fractions or decimals (0, 1, 2, 3…).
Place Value – The value of a digit based on its position in a number.
Abacus – A calculating tool with beads that slide on rods.
Remainder – In addition, this refers to the digit carried over to the next column when the sum of a column is 10 or more.
Quantitative Reasoning – The ability to understand and use numerical information to solve problems.

Differentiation

For pupils who are struggling, the teacher will provide more one-on-one support, use simplified examples with smaller numbers, and allow more time for abacus practice. For advanced pupils, the teacher will provide more complex quantitative reasoning problems and challenge them with addition problems involving more digits or multiple addends.

Note for teachers using this lesson plan

Ensure that pupils fully grasp the concept of place value before moving to addition with carrying over. Use the abacus as a visual aid to solidify understanding, especially for concrete learners. Encourage pupils to explain their steps when solving problems to reinforce their learning.