Introduction to Machines and Work

Grade 6 · General Science

Semester 2 | Period 5 | Week 25

Download the Lessonotes Mobile Liberia app for faster lesson access on Android and iPhone.

Get it on Google Play Get it on the Apple App Store

Subject: General Science

Semester: 2

Period: 5

Week: 25

School Name:
Teacher’s Name:
Subject: General science
Grade Level: Grade 6
Date: Week 25
Lesson Duration: 45 minutes
Week & Period: Week 25, Period 5
Topic: Introduction to Machines and Work
Sub-topic: Meaning of machines and work, examples of simple machines, everyday uses of machines
Learning Objectives
By the end of the lesson, students should be able to define machines and work, identify different types of simple machines, and explain how they are used in daily life.

Previous Knowledge
Students already know that humans perform tasks and use tools to make work easier.

Instructional Materials
Pictures and diagrams of simple machines, models (lever, pulley, inclined plane, wheel and axle, wedge, screw), chart paper, markers.

Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Ask learners to discuss in pairs tasks they find difficult and how tools or machines help them. Show pictures of different simple machines and ask learners to name any they recognize.

B – Building Knowledge (Main Lesson Body)

Time: 25–30 minutes

Learners’ Activities (Expanded):

  • Students observe real objects or models such as a bottle opener (lever/screw), wheelbarrow (wheel and axle/lever), pulley system (bucket and rope), and knives (wedge).
  • In groups, they classify the objects under the six types of simple machines.
  • Students try small demonstrations:
    • Use a ruler and eraser as a lever to lift a small stone.
    • Use a toy pulley to lift a cup.
    • Roll a toy car (wheel and axle) vs. dragging it without wheels.
    • Push a box up a slanted plank (inclined plane) vs. lifting it directly.
  • Teacher explains the meaning of machine and work with simple examples and guides learners in discussing how each machine makes work easier in daily life.

Assessment Checks:

  • Teacher asks learners:
  1. What is a machine?
  2. What is work in science?
  3. Mention one type of simple machine and how it is used in daily life.
  4. Why do machines make work easier?

Notes (Expanded & Detailed):

  • A machine is anything that helps us do work more easily.
  • Work (in science) happens when a force (a push or pull) moves an object through a distance. For example, lifting a chair is work, but holding it without moving is not work in science.
  • Simple machines are the basic devices that help us do work. There are six main types:
  1. Lever – a bar that turns on a support (e.g., seesaw, crowbar, bottle opener).
  2. Pulley – a wheel with a rope used for lifting (e.g., drawing water from a well).
  3. Wheel and Axle – a wheel attached to a rod to reduce friction (e.g., bicycle wheels, doorknob, rolling cart).
  4. Inclined Plane – a sloping surface used to raise or lower loads (e.g., ramp for wheelchairs, loading plank).
  5. Wedge – a sharp edge used to split or cut things (e.g., knife, axe, nail).
  6. Screw – a twisted inclined plane used for fastening or lifting (e.g., jar lid, drilling screw, car jack).
  • Simple machines are part of our everyday life:
    • Farmers use hoes (levers).
    • Carpenters use hammers and nails (levers and wedges).
    • Builders use pulleys to lift cement.
    • We use bicycle wheels for transport.
  • These machines save effort, reduce time, and help us complete tasks efficiently.

Extra Practical Activity / Assignment:

  • Learners go around the school compound or home to list at least 5 examples of simple machines, state their type, and describe how they are used.

C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Recap the meaning of machines and work, identify types of simple machines, and discuss examples of their everyday use. Emphasize how machines reduce effort.

Evaluation Method (Expanded)
Exit slip/quiz: Learners write one type of simple machine and one way it is used in daily life. Teacher collects slips and provides oral feedback.
Assignment (Expanded): Draw and label any two simple machines and describe how each is used at home or school.
Follow-up Activity: Observe and list simple machines around the school or home and share findings in the next lesson.
Differentiation / Inclusive Strategies: Provide models and diagrams for visual learners, allow group discussions, and give simplified explanations for learners needing extra support.

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