Force

Grade 4 · General Science

Semester 1 | Period 2 | Week 8

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Subject: General Science

Semester: 1

Period: 2

Week: 8

School Name:
Teacher’s Name:
Subject: General science
Grade Level: Grade 4
Date: Week 8
Lesson Duration: 45 minutes
Week & Period: Week 8, Period 2
Topic: Force
Sub-topic: Two Groups of Forces – Contact Forces

Learning Objectives
By the end of the lesson, students should be able to:
State the meaning of contact force
Give examples of contact forces
Demonstrate contact forces such as friction, tension, applied force, and normal force

Previous Knowledge
Students already know the meaning of force as a push or pull

Instructional Materials
Charts showing rubbing hands, pulling ropes, and pushing objects
Objects like ropes, books, chairs, and balls
Flashcards of contact force examples

Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Teacher asks two learners to drag a chair across the floor. Teacher asks: “What makes the chair move? What makes it hard to drag?” Learners respond. Teacher introduces contact forces.

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

  • Learners listen carefully as the teacher explains that contact forces happen when objects touch each other.
  • Learners observe practical demonstrations:
    • Friction: Teacher rubs hands together or slides a book across the desk to show resistance to motion.
    • Tension: Teacher or learners pull a rope in a tug-of-war style demonstration.
    • Applied force: Teacher pushes a desk or learners push a chair to demonstrate force applied to move an object.
    • Normal force: Teacher places a book on a table to show the support force acting upward.
  • Learners perform simple hands-on demonstrations in groups:
    • Rub hands or surfaces to feel friction.
    • Pull a rope or string to feel tension.
    • Push a light object to feel applied force.
    • Place objects on flat surfaces to observe normal force.
  • Learners discuss in pairs or groups which contact forces they use daily and write down examples:
    • Friction: walking, writing with a pencil, sliding a book
    • Tension: pulling a swing, tug-of-war, lifting a bucket with a rope
    • Applied force: opening a door, moving furniture
    • Normal force: objects resting on desks, chairs, or shelves

Assessment Checks:

  • Teacher asks: “What is a contact force?” (Expected answer: A force that happens when objects touch each other)
  • Teacher asks learners to give one example of a contact force from daily life.
  • Teacher observes learners during demonstrations to ensure correct identification and understanding of each type of contact force.

Notes (Expanded & Detailed):

  • Contact forces: Forces that occur when two objects touch each other.
  • Types of contact forces and examples:
  1. Friction: Force that resists motion between two surfaces. Example: sliding a book, walking, rubbing hands.
  2. Tension: Pulling force in a rope or string. Example: tug-of-war, lifting a bucket with a rope.
  3. Applied force: Force we apply to move objects. Example: pushing a chair, opening a door.
  4. Normal force: Support force acting on objects resting on a surface. Example: book on table, cup on desk.
  • Contact forces are everywhere in daily life and help objects move, stop, or stay in place.

Assignment/Homework:

  1. Draw and label one example of each type of contact force (friction, tension, applied force, normal force).
  2. Write down three activities at home or school where you use friction, tension, or applied force.
  3. Observe an object resting on a surface at home and describe the normal force acting on it in one sentence.

C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Teacher revises contact forces and examples. Learners identify examples of contact forces around them.

Evaluation Method (Expanded):
Exit slip/quiz: Learners write two examples of contact forces. Teacher will collect slips and provide oral feedback.

Assignment (Expanded):
Draw and label two examples of contact forces.

Follow-up Activity:
Learners observe at home one activity that involves contact force and report in the next lesson.

Differentiation / Inclusive Strategies
Teacher demonstrates with real objects. Learners with difficulty writing may describe orally.

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