Class: Junior Secondary School 2 (JSS2, JSS 2)
Term: 2nd Term
Week: 5
Age: 13 years
Duration: 45 minutes
Subject: Mathematics
Curriculum Theme: Mathematics
Previous Lesson: Solving Simple Equations and Word Problems
Topic: Linear Inequalities in One Variable
Subject Matter: Solution of linear inequalities, Graphical representation of linear inequalities, Word problems involving linear inequalities in one variable.

Specific Objectives

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

Cognitive Domain:
(a) Solve linear inequalities in one variable correctly.
(b) Interpret and represent solutions of inequalities on a number line.
Affective Domain:
(a) Appreciate the usefulness of inequalities in solving real-life problems.
Psychomotor Domain:
(a) Draw number lines and mark solution sets accurately.
Social Domain:
(a) Work cooperatively in pairs to solve inequality problems.

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
Cuemath – Meaning, Calculate, Solving, Graphing Inequalities
Relevant Textbooks

Instructional Materials

The teacher will teach this lesson with the aid of:

Number line charts
Marker and whiteboard
Flash cards containing inequality symbols
Cardboard strips showing worked examples
Ruler and pencils for drawing number lines

Rationale for the Lesson

This lesson equips pupils with the knowledge and skills to solve inequalities and interpret solution sets, which are essential for mathematical reasoning and real-life decision-making.

Prerequisite/Previous Knowledge

Pupils have previously learned simple equations, number operations, and the use of inequality symbols such as >, <, ≥, and ≤.

Lesson Content/Board Summary

Lesson Content

Linear Inequalities in One Variable

A linear inequality in one variable is a mathematical statement that shows the relationship between two quantities using inequality symbols such as >, <, ≥, or ≤.

The following are examples of linear inequalities in one variable with their solutions:

Solve: 2x + 3 > 7
2x > 4
x > 2
Solve: 5 – x ≤ 3
–x ≤ –2
x ≥ 2
Solve: 3x < 12
x < 4

Graphical Representation of Linear Inequalities

Linear inequalities can be represented on a number line to show all possible values that satisfy the inequality.

The following are examples of graphical representations:

x > 2 → Open circle at 2, shading to the right.
x ≤ –1 → Closed circle at –1, shading to the left.
x ≥ 4 → Closed circle at 4, shading to the right.

Word Problems Involving Linear Inequalities

Word problems help to apply inequalities to real-life situations such as age limits, costs, and measurements.

Examples include:

A pupil must be at least 12 years old to join a club. If x is the age, then:
x ≥ 12
A book costs ₦500, and a pupil has ₦m. For the pupil to afford the book:
m ≥ 500
A bottle can hold not more than 2 liters of water. If v is the volume:
v ≤ 2

Teaching Methods/Instructional Techniques:

Discussion, Lecture, Explanation, Demonstration, Group Work, Visualization, Question and Answer

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: Reviews previous work on equations and asks pupils to compare equations and inequalities using flash cards.
Pupils’ Activity: Respond to questions and identify inequality symbols.
Learning Point: Pupils recall concepts leading into inequalities.

Step 2: Solving Linear Inequalities

Time: 10 minutes
Teaching Skill: Explanation
Teacher’s Activity: Solves examples of linear inequalities on the board and explains each step clearly.
Pupils’ Activity: Observe and solve similar problems individually.
Learning Point: Pupils understand how to solve basic inequalities.

Step 3: Graphical Representation

Time: 10 minutes
Teaching Skill: Demonstration
Teacher’s Activity: Draws number lines and shows how to represent solutions with open or closed circles.
Pupils’ Activity: Draw number lines in their books following teacher’s demonstration.
Learning Point: Pupils learn to represent solution sets graphically.

Step 4: Word Problems on Inequalities

Time: 10 minutes
Teaching Skill: Discussion
Teacher’s Activity: Presents real-life word problems and guides pupils to translate them into inequalities.
Pupils’ Activity: Work in pairs to solve provided word problems.
Learning Point: Pupils connect inequalities with daily situations.

Step 5: Note-Taking

Time: 5 minutes
Teaching Skill: Reinforcement
Teacher’s Activity: Provides the Board Summary for pupils to copy.
Pupils’ Activity: Write notes neatly in their books.
Learning Point: Pupils maintain accurate records of concepts learned.

Step 6: Evaluation/Review

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

Solve: 4x – 6 < 10
Represent x ≥ –3 on a number line
Form an inequality: “A pupil must have more than ₦200 to buy a snack.”
Pupils’ Activity: Answer questions orally.
Learning Point: Pupils demonstrate mastery of learning objectives.

Step 7: Conclusion

Time: 2 minutes
Teaching Skill: Reinforcement
Teacher’s Activity: Summarizes key points and encourages pupils to practice more inequality problems.
Pupils’ Activity: Listen and ask final questions.
Learning Point: Pupils understand the need for continuous practice.

Lesson Keywords

Inequality – a mathematical comparison showing greater or lesser values
Variable – a symbol representing an unknown quantity
Solution Set – all possible values that satisfy an inequality
Number Line – a line used to show numerical values and solutions
Expression – a combination of numbers, variables, and operations

Differentiation

Provide simpler inequality problems for slow learners, while faster learners handle complex multi-step inequalities and additional word problems.

Note for teachers using this lesson plan

Emphasize the difference between open and closed circles. Encourage neat drawing of number lines and ensure pupils follow steps when solving inequalities.