Force

Grade 4 · General Science

Semester 1 | Period 2 | Week 10

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Subject: General Science

Semester: 1

Period: 2

Week: 10

School Name:
Teacher’s Name:
Subject: General science
Grade Level: Grade 4
Date: Week 10
Lesson Duration: 45 minutes
Week & Period: Week 10, Period 2
Topic: Force
Sub-topic: Measurement of Force – Unit of Force

Learning Objectives
By the end of the lesson, students should be able to:
State the unit of force
Explain Newton as the unit of force
Give examples of measuring force in Newtons

Previous Knowledge
Students already know about different groups of forces

Instructional Materials
Charts showing the symbol N for Newton
Pictures of Newton scale
Flashcards of force measurement examples

Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher shows a picture of a weighing scale and asks: “How do we measure weight?” Learners respond. Teacher introduces Newton as the unit of force.

B – Building Knowledge (Main Lesson Body)
Time: 25–30 minutes
Learners’ Activities (Expanded):

  • Learners listen carefully as the teacher explains that force is measured in Newtons (N), a unit named after Sir Isaac Newton.
  • Learners observe pictures, charts, and diagrams showing objects being pushed or pulled with the force measured in Newtons.
  • Learners participate in simple exercises comparing forces:
    • Teacher or learners push light and heavy objects and discuss which object requires more force.
    • Learners estimate which object would need more Newtons to move: a small box or a large box, a pencil or a chair.
  • Learners discuss examples of objects that require more or less force to move in daily life:
    • Pushing a car requires more force than pushing a toy car.
    • Lifting a book requires less force than lifting a full bag of rice.
  • Learners record their observations and answers in their notebooks.

Assessment Checks:

  • Teacher asks: “What is the unit of force?” (Expected answer: Newton)
  • Teacher asks: “What is the symbol of Newton?” (Expected answer: N)
  • Teacher asks learners to give one example of an object that requires more force and one that requires less force to move.
  • Teacher observes learners during exercises to ensure understanding of force measurement and comparisons.

Notes (Expanded & Detailed):

  • Unit of force: Force is measured in Newtons (N), named after Sir Isaac Newton, the scientist who studied motion.
  • Key points:
    • A larger or heavier object requires more force to move than a smaller or lighter object.
    • A lighter object requires less force to move.
    • Understanding how much force is needed helps in planning work, lifting objects, or designing machines.
  • Examples learners can relate to:
    • Pushing a chair (few Newtons) vs. pushing a car (hundreds of Newtons)
    • Lifting a pencil (few Newtons) vs. lifting a school bag full of books (more Newtons)
  • Observation tip: Notice how much effort is needed to move different objects at home or school.

Assignment/Homework:

  1. List five objects at home or school and predict whether they require more or less force to move.
  2. Draw two objects: one that requires a small force to move and one that requires a large force, and label them with “N” for Newton.
  3. With help from an adult, push or lift three objects at home and describe which needed more effort and why, using the term Newtons.

C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Teacher revises the unit of force and explains that it is measured in Newtons. Learners practice giving examples.

Evaluation Method (Expanded):
Exit slip/quiz: Learners write the unit of force and its symbol. Teacher will collect slips and provide oral feedback.

Assignment (Expanded):
Learners write three examples of objects and how much force they think is needed to move them.

Follow-up Activity:
Learners observe at home which objects need more or less force to move.

Differentiation / Inclusive Strategies
Teacher explains with charts and examples for better understanding. Learners who cannot write can respond orally.

Teacher’s Reflection (After Class)
What worked well? ___________________________________________
What needs improvement? ____________________________________
Students’ engagement level: ☑ High ☑ Medium ☑ Low