Mathematics - Primary 5 - Binary numbers

Term: 3^rd Term

Week 7

Class: Primary 5
Age: 10 years
Duration: 40 minutes of 5 periods
Date:
Subject: Mathematics
Topic: Binary Numbers

SPECIFIC OBJECTIVES:

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

Explain the concept of a number system.
Identify numbers written in base ten and base two.
Convert numbers from base two to base ten and vice versa.
Add and subtract numbers in base two.
Solve quantitative aptitude problems related to binary numbers.

INSTRUCTIONAL TECHNIQUES:

Demonstration
Group activities
Guided discovery
Problem-solving approach
Interactive discussions

INSTRUCTIONAL MATERIALS:

Place value charts (base ten and base two)
Flashcards with binary and decimal numbers
Counters or bottle caps
Number conversion tables
Whiteboard, markers, erasers
Binary puzzle worksheets

INSTRUCTIONAL PROCEDURES:

PERIOD 1 and 2

PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 – INTRODUCTION	Introduces number systems and explains how numbers are written in different bases (e.g., base 10, base 2).	Pupils listen and respond with examples of where they’ve seen 0s and 1s (e.g., in phones, computers).
STEP 2 – EXPLANATION	Demonstrates how base 10 works and introduces binary (base 2), explaining that it only uses 0 and 1.	Pupils compare base 10 and base 2 and identify differences.
STEP 3 - DEMONSTRATION	Shows examples of numbers in base 10 and their binary equivalents using a conversion chart.	Pupils practice identifying whether numbers are base 10 or base 2.
STEP 4 - NOTE TAKING	Teacher summarizes key differences between base 10 and base 2 on the board.	Pupils copy notes and ask questions for clarity.

NOTE (On the Board):

Base 10 uses digits 0–9
Base 2 (Binary) uses only digits 0 and 1
Examples:

2 in base 10 = 10 in base 2
5 in base 10 = 101 in base 2

EVALUATION:

Pupils state two differences between base 10 and base 2.
Pupils classify a list of numbers as base 10 or base 2.

CLASSWORK:

Identify which of the following are in base 2 or base 10: 1101, 27, 1001, 58

ASSIGNMENT:

Find 5 numbers written in binary and write what you think they might mean in base 10.

CONCLUSION:
Teacher praises pupils’ effort and encourages them to think of binary like a secret number code.

PERIOD 3 and 4

PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 – INTRODUCTION	Reviews binary number concept, then introduces conversion between base 2 and base 10.	Pupils share their understanding and past homework.
STEP 2 – EXPLANATION	Explains conversion from base 2 to base 10 by expanding in powers of 2.	Pupils watch and follow examples step-by-step.
STEP 3 - DEMONSTRATION	Demonstrates 2–3 conversion examples (e.g., 1011₂ = 11₁₀). Then, shows base 10 to base 2 conversion.	Pupils help solve conversions with teacher guidance.
STEP 4 - NOTE TAKING	Pupils write down conversion steps and examples.	Pupils copy notes and ask clarifying questions.

NOTE (On the Board):

Base 2 to Base 10:

1101₂ = 1×8 + 1×4 + 0×2 + 1×1 = 13

Base 10 to Base 2:

13₁₀ → divide by 2:

13 ÷ 2 = 6 R1
6 ÷ 2 = 3 R0
3 ÷ 2 = 1 R1
1 ÷ 2 = 0 R1
Read bottom to top = 1101₂

EVALUATION:

Pupils convert the following:

1110₂ = ?
14₁₀ = ?

CLASSWORK:

Convert:

1001₂ → ?
15₁₀ → ?

ASSIGNMENT:

Convert the following base 10 numbers to binary: 7, 10, 18
Convert these binary numbers to base 10: 101, 1000, 1111

CONCLUSION:
Teacher applauds learners’ effort and encourages them to practice more conversions.

PERIOD 5

PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 – INTRODUCTION	Introduces binary addition and subtraction.	Pupils listen attentively.
STEP 2 – EXPLANATION	Explains rules of binary addition and subtraction: 0+0=0, 1+0=1, 1+1=10 1−0=1, 1−1=0, 10−1=1 0- 1 = (borrow like in base 10)	Pupils listen and ask questions.
STEP 3 - DEMONSTRATION	Solves sample binary sums and differences on the board	Pupils follow the steps and help solve examples.
STEP 4 - NOTE TAKING	Pupils write binary addition/subtraction rules.	Pupils copy notes and complete practice exercises.

NOTE (On the Board):

Binary Addition Examples:

101₁₂ + 11₂ = 1000₂

Binary Subtraction Example:

1011₂ – 10₂ = 1001₂

EVALUATION:

Pupils solve binary additions:

110 + 101 = ?
1001 – 10 = ?

CLASS ACTIVITY:

Group work on binary addition and subtraction challenges.

CLASSWORK:

Solve:

11₂ + 101₂ = ?
1110₂ – 11₂ = ?

ASSIGNMENT:

Solve 3 binary addition and 3 binary subtraction problems from your worksheet.

CONCLUSION:
Teacher concludes the week’s topic and praises the pupils. Pupils are encouraged to relate binary numbers to digital devices and games.

SUMMARY OF LESSON:

This week, pupils learned the concept of number systems with focus on binary (base 2). They practiced identifying base 10 and base 2 numbers, converting between them, and performing basic arithmetic operations in binary. Through interactive activities and real-life connections, pupils developed a foundational understanding of binary numbers used in computing and digital technology.