Simple Machines Lesson Plan: The Inclined Plane and the Screw

Submitted by: Deena L. Kay

Grade Levels: 3-5, 6-8, K-3

In this lesson plan, which is adaptable for grades K-8, students use BrainPOP Jr. and/or BrainPOP resources to explore the inclined plane and the screw as simple machines. Students will analyze how the inclined plane makes work easier. They will also compare and contrast the inclined plane and the screw.

Students will:

  1. Identify the inclined plane and the screw as simple machines
  2. Analyze how the inclined plane makes work easier
  3. Compare the inclined plane and the screw

Materials:

  • Subscription to BrainPOP and BrainPOP Jr.
  • Access to computers
  • 3 large books (such as dictionaries)
  • A load/weight (this should be something you can tie to a piece of string around so you can attach it to the spring scale)
  • String/yarn
  • Spring scale
  • Copies of 2 different triangles: one 3 inches high/4 inches long, the other 3 inches high/6 inches long (1 copy of each per student)
  • Markers or highlighters
  • Pencils (2 per student)
  • Tape

Vocabulary:

load; effort; inclined plane; screw; wedge

Preparation:

Tie a piece of string around your load so it can be attached to your spring scale.

Lesson Procedure:

  1. Introduce simple machines as machines with few or no moving parts, that make work easier. There are only 6 simple machines: inclined plane, screw, wedge, lever, pulley and wheel and axle. Today, we will be learning about 2 of these--the inclined plane and the screw.
  2. Watch Brainpop Jr. movie entitled Simple Machines. Then, watch the Brainpop movie entitled Inclined Plane and take the Quiz (or take the quiz first as a quick pre-assessment to see what students already know).
  3. Demonstrate how the inclined plane makes work easier.
    a. First, use the spring scale to weigh the item you are using as a load. b. Then, create an inclined plane by stacking 2 of the large books in a pile. Lean the third book against the 2 stacked books to create a ramp.
    c. Keeping the load attached to the spring scale, slowly slide the load up the inclined plane. As you are sliding, have students read the weight of the load.
    d. Ask: How does the inclined plane make work easier?
  4. Discuss the relationship between the inclined plane and the screw--the screw is simply an inclined plane wrapped around a center pole, with a wedge at the tip.
  5. Have students use the 2 triangles to make models of screws.
  6. Have students use a marker or highlighter to highlight the longest side of each triangle.
  7. Cut out both triangles. Point out that these are inclined planes. Ask students: If these were mountains, which would you rather climb? Why? (You would want to climb up the longer one--although it would take longer, the work is also more spread out).
  8. First, create a "screw" from the smaller triangle. Tape the triangle/inclined plane to the pencil (like a sail). Then, wrap the inclined plane around the pencil, ensuring that the highlighted side faces out. Tape the tip so that it stays wrapped. The highlighting along the longest side of the inclined plane represents the threads of the screw.
  9. Do the same with the longer inclined plane. This screw should have "threads" that are closer together.
  10. Ask students: If you were building something, which of these do you think would be easier to turn? Why? (The screw with the threads closer together would be easier to turn; however you would have to turn it a greater number of times.)
  11. Ask students: How are a screw and an inclined plane alike? How are they different?

Extension Activity:

Have students go on a "scavenger hunt" around the school building to look for examples of inclined planes, screws, and/or other simple machines. Check out BrainPOP Jr's Background Information and Activities for additional suggested activities at home and at school.