Mathematics - Primary 6 - Open Sentences

Term: 2^nd Term

Week 4

Class: Primary 6
Age: 11 years
Duration: 40 minutes for 5 periods
Date:
Subject: Mathematics
Topic: Open Sentences

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

Interpret word problems and real-life situations into open sentences.
Solve addition and subtraction open sentences.
Solve multiplication and division open sentence exercises.
Understand and use reciprocals of numbers.
Solve quantitative reasoning questions related to open sentences.

INSTRUCTIONAL TECHNIQUES:
• Demonstration
• Group activities
• Problem-solving approach
• Use of teaching aids (charts, flashcards, whiteboard)
• Interactive discussions

INSTRUCTIONAL MATERIALS:
• Chart with open sentence examples
• Flashcards with equations
• Markers, whiteboard, and erasers
• Worksheet for exercises

INSTRUCTIONAL PROCEDURES:

PERIOD 1 and 2: PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 - INTRODUCTION	Introduce the concept of open sentences by explaining an equation where the value of a variable is unknown.	Pupils listen and ask questions for clarification.
STEP 2 - EXPLANATION	Demonstrate how to form open sentences from word problems (e.g., "The sum of a number and 5 is 10," becomes x + 5 = 10).	Pupils observe and take notes.
STEP 3 - DEMONSTRATION	Solve open sentences in addition and subtraction.	Pupils follow along and practice solving the open sentences.
STEP 4 - NOTE TAKING	Write down examples and steps for solving open sentences.	Pupils take notes.

NOTE (On the Board):
• Open sentence: An equation where a value is unknown, often represented by a variable (e.g., x + 5 = 10).
• Solve: x = 10 - 5 → x = 5
• Example: The sum of a number and 8 is 15. Solve for the number. (x + 8 = 15).

EVALUATION:
• Ask pupils to solve word problems by forming open sentences.
CLASSWORK:
• Solve the following:

The difference between a number and 6 is 12. Find the number.
ASSIGNMENT:
• Write 5 word problems and translate them into open sentences.

CONCLUSION:
The teacher praises the pupils for understanding open sentences and encourages them to practice solving them.

PERIOD 3 and 4: PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 - INTRODUCTION	Recap the previous lesson and introduce multiplication and division open sentences.	Pupils recall previous knowledge and participate in a discussion.
STEP 2 - EXPLANATION	Demonstrate how to solve open sentences involving multiplication and division.	Pupils watch and take notes.
STEP 3 - DEMONSTRATION	Solve examples involving multiplication and division.	Pupils observe and attempt the problems on their own.
STEP 4 - NOTE TAKING	Write down multiplication and division open sentence examples.	Pupils take notes.

NOTE (On the Board):
• Multiplication open sentence: 5 × x = 25 → x = 25 ÷ 5 → x = 5
• Division open sentence: x ÷ 4 = 3 → x = 3 × 4 → x = 12

EVALUATION:
• Ask pupils to solve multiplication and division open sentences.
CLASSWORK:
• Solve the following:

3 × x = 24. Find x.
x ÷ 5 = 8. Find x.
ASSIGNMENT:
• Solve 5 multiplication and division open sentences.

CONCLUSION:
The teacher praises the pupils for their understanding of multiplication and division open sentences.

PERIOD 5: PRESENTATION

Step	Teacher’s Activity	Pupil’s Activity
STEP 1 - INTRODUCTION	Introduce reciprocals of numbers and their use in solving equations.	Pupils listen and ask questions for clarification.
STEP 2 - EXPLANATION	Explain the reciprocal of a number (e.g., the reciprocal of 2 is 1/2).	Pupils observe and take notes.
STEP 3 - DEMONSTRATION	Demonstrate how to use reciprocals in solving open sentences.	Pupils practice using reciprocals in exercises.
STEP 4 - NOTE TAKING	Write down the reciprocal and examples.	Pupils take notes.

NOTE (On the Board):
• Reciprocal of a number: 1 ÷ number (e.g., reciprocal of 3 is 1/3).
• Example: Solve x × 2 = 6 → x = 6 × 1/2 → x = 3.

EVALUATION:
• Ask pupils to solve problems using reciprocals.
CLASSWORK:
• Solve the following:

x × 5 = 20. Find x.
ASSIGNMENT:
• Write 3 problems involving reciprocals and solve.

CONCLUSION:
The teacher commends pupils for their effort in understanding open sentences and reciprocals.