Class: Junior Secondary School 2 (JSS 2)
Term: 2nd Term
Week: 3
Age: 13 years
Duration: 45 minutes
Subject: Basic Science And Technology
Curriculum Theme: Basic Science
Previous Lesson: Potential and Kinetic Energy
Topic: Calculations Involving Work Done
Subject Matter: Calculations Involving Work Done

Specific Objectives

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

Cognitive Domain:
(a) Define physical work in simple scientific terms.
(b) Calculate work done using the formula ( W = F \times d ).
Affective Domain:
(a) Appreciate the relationship between force, distance, and work in everyday tasks.
(b) Show interest in solving word problems involving work done.
Psychomotor Domain:
(a) Use a spring balance and a ruler or meter rule to measure force and distance in a simple practical.
(b) Perform a hands‑on demonstration (e.g., pulling an object) to compute work done.
Social Domain:
(a) Work in pairs or small groups to solve problems on work done, discussing their reasoning.
(b) Share and critique different strategies for measuring and calculating work in class.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum
Lagos State Unified Scheme of Work for Junior Secondary Schools
Britannica – “Work | Definition, Formula, & Units” (Encyclopedia Britannica)
Relevant Textbooks: JSS Basic Science Textbook (Physics section on Work and Energy)

Instructional Materials

The teacher will teach this lesson with the aid of:

Spring balance (to measure force)
A small object or load (e.g., a block)
Meter rule or measuring tape (to measure distance)
Chalkboard & chalk / Whiteboard & marker
Simple calculation handout or worksheet with worked examples

Rationale for the Lesson

Understanding how to calculate work done helps pupils link force and motion to energy transfer in real life.

Prerequisite/Previous Knowledge

Pupils know what a force is (e.g., pushing or pulling) and have seen objects move when force is applied; they can also measure distance using a metre rule.

Lesson Content/Board Summary

Calculations Involving Work Done

Work in physics is done when a force causes an object to move in the direction of that force.
The symbol for work is W.

Formula for Work

Work done ( (W) ) is given by the formula:
[
W = F \times d
]
where:

F = force applied (in Newtons, N)
d = distance moved in the direction of the force (in metres, m)

Units of Work

The SI unit of work is the joule (J)
A joule is the work done when a force of 1 N moves an object through 1 m in the direction of the force.

Examples of Calculating Work

The following are simple examples:

If a force of 10 N pushes a box through a distance of 5 m in the same direction, then the work done is:
[
W = 10 \times 5 = 50;J
]
If a force of 200 N pulls a load for 12 m, work done = (200 \times 12 = 2400;J).

Teaching Methods/Instructional Techniques

Discussion, Lecture, Visual Aids, Group Work, Hands-on Practical, Problem Solving

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 asks pupils to imagine pushing a box across the floor and asks: “When have you felt like you are doing ‘work’ when pushing something? What does that feel like?” Then the teacher links their experience to the scientific meaning of work.
Pupils’ Activity: Pupils respond with real-life experiences, e.g., pushing a chair, lifting a bag, dragging a suitcase.
Learning Point: Establishes their everyday notion of work and transitions to the physics definition.

Step 2: Definition and Concept Explanation

Time: 7 minutes
Teaching Skill: Explanation
Teacher’s Activity: Defines work scientifically, writing “Work is done when a force moves an object in the direction of the force.” Presents the formula ( W = F \times d ) on the board.
Pupils’ Activity: Copy definition and formula into their notebooks; ask clarifying questions.
Learning Point: Pupils understand the core definition and formula of work.

Step 3: Demonstration (Practical)

Time: 8 minutes
Teaching Skill: Visual Aid / Hands-on
Teacher’s Activity: Using a spring balance and a small object, the teacher applies a force (measured via the balance) and moves the object a known distance. The teacher measures the distance and calculates the work done while thinking aloud.
Pupils’ Activity: Observe, note measurements, and help compute the work.
Learning Point: Connects theoretical formula to real-world measurement.

Step 4: Worked Examples (Calculation)

Time: 10 minutes
Teaching Skill: Lecture / Problem Solving
Teacher’s Activity: Presents 2–3 problems on the board (similar to examples in the board summary) and solves them step by step, showing how to plug in force and distance.
Pupils’ Activity: Follow the working, copy the worked examples, and try to solve one or two in their exercise books.
Learning Point: Pupils practice applying the formula to compute work.

Step 5: Note-Taking

Time: 5 minutes
Teaching Skill: Guided Note-Taking
Teacher’s Activity: Summarizes the key definitions, formula, units, and example calculations on the board for pupils to copy.
Pupils’ Activity: Write down the summary, ensuring they have the definition, formula, and units correctly.
Learning Point: Pupils consolidate the theoretical content in their own notes.

Step 6: Evaluation/Review

Time: 8 minutes
Teaching Skill: Questioning / Assessment
Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

What is the scientific definition of work?
Write down the formula for work done.
If a force of 15 N moves an object 4 m, how much work is done?
What is the unit of work and why?
Why is no work done if there is no displacement even if force is applied?
Pupils’ Activity: Answer orally or write; solve the numerical problem.
Learning Point: Checks understanding of definition, formula, calculation, and concept of displacement.

Step 7: Conclusion

Time: 3 minutes
Teaching Skill: Summarizing
Teacher’s Activity: Recaps the key points: the meaning of work, formula, units, and how to calculate. Encourages pupils to look out for “work” in real life (lifting, pushing) and relate it to this concept.
Pupils’ Activity: Listen and reflect, possibly give examples from their daily life.
Learning Point: Reinforces the lesson’s core ideas and connects them to everyday activities.

Lesson Keywords

Work – energy transferred by force over distance
Force – a push or pull measured in Newtons
Distance / Displacement – how far an object moves in the direction of force
Joule – the unit of work (J)
Energy transfer – the movement of energy when work is done

Differentiation

For slower learners: Use simpler numerical problems with smaller force and distance; demonstrate more with the spring balance.
For faster learners: Give word problems involving varying forces or ask them to compute with angle (if advanced) using (W = F \cdot d \cdot \cos \theta).
Pair work: Mix pupils of different ability so they can help each other in solving problems.

Note for Teachers Using This Lesson Plan

Ensure safety during the practical: don’t choose too heavy an object so pupils can move it safely.
Encourage pupils to verbalize their reasoning when solving numerical problems — this helps with conceptual clarity.
Relate examples to everyday activities in the Nigerian context (e.g., carrying water, lifting school bags, dragging furniture) to make the concept more concrete.