Mathematics - Primary 6

Term: 1^st Term

Week 5

Class: Primary 6
Age: 11 years
Duration: 40 minutes of 5 periods
Subject: Mathematics
Topic: LCM and HCF

SPECIFIC OBJECTIVES:

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

Find the LCM of 2 or 3-digit numbers using the multiple method.
Find the LCM using prime factorization.
Find the HCF using the factor method.
Solve real-life problems involving LCM and HCF.
Solve quantitative reasoning questions related to LCM and HCF.

INSTRUCTIONAL TECHNIQUES:

Step-by-step demonstration
Group discussion
Guided practice
Problem-solving approach
Real-life application

INSTRUCTIONAL MATERIALS:

Flashcards with numbers
Multiples and factors chart
Prime number chart
Worksheets
Counters or cubes
Whiteboard, markers, and erasers

INSTRUCTIONAL PROCEDURES:

PERIOD 1 and 2

PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 – INTRODUCTION	Reviews meaning of multiples and factors. Introduces LCM using the multiple method.	Pupils recall and give examples of multiples.
STEP 2 – EXPLANATION	Explains how to list multiples to find the LCM.	Pupils listen and ask questions.
STEP 3 - DEMONSTRATION	Solves: LCM of 6 and 8 → 6: 6, 12, 18, 24... 8: 8, 16, 24... LCM = 24	Pupils solve similar examples.
STEP 4 - NOTE TAKING	Provides notes and guides pupils in writing.	Pupils copy notes and examples.

NOTE (On the Board):
To find LCM using multiple method:

List multiples of each number
Find the smallest common multiple

EVALUATION:

Find LCM of:

4 and 10
12 and 16

CLASSWORK:

LCM of 3-digit numbers using the multiple method

ASSIGNMENT:

List the multiples and find the LCM of:

45 and 60
36, 54 and 90

CONCLUSION:
Teacher reinforces understanding of multiples and their importance.

PERIOD 3

PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 – INTRODUCTION	Introduces LCM using prime factorization method.	Pupils discuss what prime numbers are.
STEP 2 – EXPLANATION	Demonstrates how to break numbers into prime factors and use them to find LCM.	Pupils follow steps and practice examples.
STEP 3 - DEMONSTRATION	Example: LCM of 18 and 24
18 = 2 × 3 × 3
24 = 2 × 2 × 2 × 3
LCM = 2 × 2 × 2 × 3 × 3 = 72	Pupils solve similar problems.

NOTE:
LCM = product of all prime factors (use the highest power of each)

EVALUATION:

LCM of 16 and 20 using prime factorization

CLASSWORK:

LCM of 36 and 48 using prime factor method

ASSIGNMENT:

Find the LCM of 42 and 56 using prime factors

CONCLUSION:
Teacher highlights the accuracy of the prime factor method.

PERIOD 4

PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 – INTRODUCTION	Introduces HCF using the factor method.	Pupils mention what factors are.
STEP 2 – EXPLANATION	Explains how to list factors and find common ones.	Pupils listen and take notes.
STEP 3 - DEMONSTRATION	HCF of 12 and 18
12: 1, 2, 3, 4, 6, 12
18: 1, 2, 3, 6, 9, 18
HCF = 6	Pupils practice on their own.

EVALUATION:

Find the HCF of 20 and 30

CLASSWORK:

Find HCF of 42 and 56

ASSIGNMENT:

HCF of 81 and 108

CONCLUSION:
Teacher encourages pupils to always verify answers.

PERIOD 5

PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 – INTRODUCTION	Connects LCM and HCF to real-life problems (e.g., schedules, packaging).	Pupils give practical examples.
STEP 2 - DEMONSTRATION	“Two buses arrive at intervals of 20 mins and 30 mins. When will they arrive together?” → LCM = 60 mins	Pupils solve similar word problems.

EVALUATION:

Solve 3 real-life problems involving LCM or HCF

CLASSWORK:

Real-life and QR questions involving LCM and HCF

ASSIGNMENT:

Solve 2 real-life problems on HCF and LCM

CONCLUSION:
Teacher reviews the week's lessons and gives feedback.

Mathematics - Primary 6 - LCM and HCF