Class: Junior Secondary School 2 (JSS2, JSS 2)
Term: 1st Term
Week: 5
Age: 13 years
Duration: 45 minutes
Subject: Mathematics
Curriculum Theme: Mathematics
Previous Lesson: Factors, Multiples, LCM, Squares and Square Roots
Topic: Directed Numbers
Subject Matter: Addition and subtraction of directed numbers, Multiplication and division of directed numbers, Simplifying expression with directed numbers.

Specific Objectives

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

Cognitive Domain:
(a) State the rules governing the addition and subtraction of directed numbers.
(b) Solve problems involving multiplication and division of directed numbers.
(c) Simplify mathematical expressions that contain directed numbers.
Affective Domain:
(a) Show confidence and accuracy when performing operations with directed numbers.
Psychomotor Domain:
(a) Apply rules of directed numbers in solving examples on the board or worksheets.
Social Domain:
(a) Work cooperatively in groups to solve directed number exercises.

Reference Materials

The following resources was used in planning this lesson:

9 Years Basic Education Curriculum
Lagos State Unified Scheme of work for Junior Secondary Schools
WJEC – DIRECTED NUMBERS
Relevant Textbooks

Instructional Materials

The teacher will teach this lesson with the aid of:

Number line chart
Flash cards with positive and negative numbers
Whiteboard and markers
Exercise worksheets
Simple counters or bottle caps representing positive and negative values

Rationale for the Lesson

This lesson helps students develop the ability to handle operations involving directed numbers, which are fundamental in solving real-life and mathematical problems involving gains, losses, temperature changes, and elevations.

Prerequisite/Previous Knowledge

Pupils have been introduced to the concept of positive and negative numbers and can represent them correctly on a number line.

Lesson Content/Board Summary

Directed Numbers

Directed numbers are numbers that have both size (magnitude) and direction. They include positive numbers (+) and negative numbers (−). Positive numbers are greater than zero, while negative numbers are less than zero.

Addition and Subtraction of Directed Numbers

When adding or subtracting directed numbers, we must consider their signs. The signs determine whether the numbers will be added or subtracted.

The following are the rules for addition and subtraction of directed numbers:

When the signs are the same, add the numbers and keep the common sign.
- Example: (+3) + (+5) = +8, (−3) + (−4) = −7.
When the signs are different, subtract the smaller number from the larger one and take the sign of the larger number.
- Example: (+8) + (−5) = +3, (−9) + (+4) = −5.
Subtracting a number means adding its opposite.
- Example: (+6) − (−3) = +6 + 3 = +9.

Multiplication and Division of Directed Numbers

Multiplication and division of directed numbers follow sign rules. The result depends on whether the signs of the numbers involved are the same or different.

The following are the rules for multiplication and division of directed numbers:

When the signs are the same, the answer is positive.
- Example: (+5) × (+2) = +10, (−6) ÷ (−3) = +2.
When the signs are different, the answer is negative.
- Example: (+8) × (−2) = −16, (−9) ÷ (+3) = −3.

Simplifying Expressions with Directed Numbers

In simplifying expressions with directed numbers, apply the rules of addition, subtraction, multiplication, and division carefully according to the order of operations (BODMAS).

Examples include:

(+4) − (−3) + (−2) = +4 + 3 − 2 = +5
(−6) × (+2) ÷ (−3) = (−12) ÷ (−3) = +4

Teaching Methods/Instructional Techniques:

Lecture, Discussion, Explanation, Demonstration, Question and Answer, Guided Practice, Group Work

Instructional Procedures

To deliver this lesson, the teacher will adopt the following steps:

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher reviews the previous lesson on number representation on the number line and introduces the concept of directed numbers using real-life examples such as temperature rise and fall.
Pupils’ Activity: Pupils respond to questions and share examples of situations involving positive and negative changes.
Learning Point: Pupils recall previous knowledge and connect it with the new topic.

Step 2: Addition and Subtraction of Directed Numbers

Time: 10 minutes
Teaching Skill: Explanation
Teacher’s Activity: The teacher explains and demonstrates addition and subtraction of directed numbers using the number line and examples.
Pupils’ Activity: Pupils follow examples, solve simple exercises, and give their own examples.
Learning Point: Pupils learn how to apply sign rules for addition and subtraction.

Step 3: Multiplication and Division of Directed Numbers

Time: 10 minutes
Teaching Skill: Discussion and Demonstration
Teacher’s Activity: The teacher explains the rules for multiplication and division of directed numbers using examples on the board.
Pupils’ Activity: Pupils respond and solve related exercises.
Learning Point: Pupils understand the rules governing multiplication and division of directed numbers.

Step 4: Simplifying Expressions with Directed Numbers

Time: 10 minutes
Teaching Skill: Guided Practice
Teacher’s Activity: The teacher guides pupils through simplification of expressions involving directed numbers using BODMAS rule.
Pupils’ Activity: Pupils work on class exercises and discuss answers in groups.
Learning Point: Pupils can simplify expressions correctly following the order of operations.

Step 5: Note-Taking

Time: 5 minutes
Teaching Skill: Explanation
Teacher’s Activity: The teacher dictates or writes the board summary for pupils to copy into their notes.
Pupils’ Activity: Pupils copy the board summary neatly.
Learning Point: Pupils have a complete written record of the lesson.

Step 6: Evaluation/Review

Time: 3 minutes
Teaching Skill: Questioning
Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

State the rule for adding directed numbers with the same sign.
What is the result of multiplying two numbers with different signs?
Simplify: (+5) − (−3).
Solve: (−4) × (−2) ÷ (+4).
Pupils’ Activity: Pupils respond to the questions orally or on the board.
Learning Point: Pupils’ understanding of the lesson objectives is verified.

Step 7: Conclusion

Time: 2 minutes
Teaching Skill: Reinforcement
Teacher’s Activity: The teacher summarizes the lesson and encourages pupils to practice more examples at home.
Pupils’ Activity: Pupils listen and ask clarifying questions.
Learning Point: Pupils understand and appreciate the importance of mastering directed numbers.

Lesson Keywords

Directed numbers – numbers with direction, either positive or negative
Positive number – a number greater than zero
Negative number – a number less than zero
BODMAS – order of operations in simplifying expressions
Sign rule – rule guiding the operation of directed numbers

Differentiation

Teacher uses simpler examples for slower learners, while fast learners solve more complex expressions and explain solutions to peers.

Note for teachers using this lesson plan

Use visual aids like number lines and color-coded counters to help pupils grasp the concept of positive and negative directions. Always relate the topic to real-life examples like gains and losses.