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L7 Gear Image


Introduction: The sixth, and final, simple machine is the wheel and axle. Students will aslo be introduced to gears, which are a type of wheel that can work independently from an axle.
Curriculum Subject and Topic: Science—Simple Machines
Estimated Duration: 50 minutes
Grade Level: 3

Curriculum Goals: Ohio Academic Content Standards

Lesson Objectives: Students will


Accommodations for Special Learners

Setting the Stage

  1. Prepare a station for students to experiment with flattening dough or clay with a rolling pin.
  2. Make a copy of the wheels at home worksheet for each student.
  3. Students will need to have a page ready for their Unit Journals to discuss their learning during the lesson.

Lesson Activities

Activity 1

  1. Reshow the video from the Intro lesson if students need to review the concepts for wheel and axle/gears before starting Lesson 7. Tell students that we consider gears to be a type of wheel, only a wheel that can act as a simple machine on its own because of the teeth in each gear interlocking with other gears. If possible, show students the inside of a watch or a clock to demonstrate how gears work. Note: While we introduce the concept of gears, the focus of the lesson is truly on wheels and axle for the lesson.
  2. Take students to the prepared center with the dough or clay and rolling pin.
  3. Make sure the dough or clay starts as a ball.
  4. Call on a student to come up and try to flatten the ball with her or his hands only. Point out to students how long it takes and how hard the student is working.
  5. Have the student reform the ball, then use the rolling pin to show the class how quickly and easily you can flatten the ball with the rolling pin.
  6. Allow each student an opportunity to go up and try the experiment.

Activity 2

  1. Pass out the wheels at home worksheets to students.
  2. Tell students what each object on tehir paper is. Name the clip art images for can opener, pizza cutter, door knob, and bicycle. Discuss with students that these items represent common household objects.
  3. Ask students to put an X on the wheels on each image.
  4. Finally, have the students think of two additional machines at their homes that have wheels and axles. Direct them to draw the objects in the boxes at the bottom of the worksheet. Make sure they also label the images.

Wrap Up

Allow students the opportunity to share their drawings with one another and discuss how they make work easier, and what type of work that is. As a culminating Unit Journal activity, have students write a paragraph explaining what they have learned about simple machines and why they are important and valuable.

Supplemental Activities: Extension and Remediation

Gears: If you would like to extend the lesson by experimenting with gears, this simple activity with bubbles and a rotary eggbeater is a fun way to do that. Fill two bowls of the same size about half full with water and about a half teaspoon of dish soap. Give two children a rotary eggbeater. Set a stopwatch for 20 seconds. Have two students compete against each other to see who can make the most bubbles in that period of time. Repeat with other pairs of students.

Assessment and Evaluation

  1. Unit Journal Entry: This is a great opportunity to assess what students have learned about simple machines and how they help us make work easier.
  2. Wheels at Home Worksheets: Review student responses, noting any errors and provided appropriate feedback.

[Return to Ed Tech 506] [Intro] [Lesson 1] [Lesson 2] [Lesson 3] [Lesson 4] [Lesson 5] [Lesson 6] [Closure]