Photograph of jigsaw puzzle pieces.

CareerStart lessons: Grade seven

LEARN NC was a program of the University of North Carolina at Chapel Hill School of Education from 1997 – 2013. It provided lesson plans, professional development, and innovative web resources to support teachers, build community, and improve K-12 education in North Carolina. Learn NC is no longer supported by the School of Education – this is a historical archive of their website.

Learning outcomes

Students will gain an understanding of simple machines.

Teacher preparation

Time required for lesson

Two class periods (45-55 minutes each). Homework time may be required.

Materials needed

  • Computer with internet access
  • Student handouts:
    • Simple machine puzzle
    • “Building a Catapult” — instructions and worksheet
    • “Careers with Simple Machines” worksheet
  • Simple machines answer key
  • Scissors
  • Graph paper
  • Notebook paper
  • Catapult materials (for each group):
    • 50 cm of masking tape (have students measure the amount of tape)
    • One cotton ball
    • One painter stick
    • One paper cup
    • One card stock
    • Two paper clips
    • One tack
    • One plastic spoon
    • Four rubber bands


  1. Hand out the simple machine puzzle. Ask the students to cut out the picture, title, and description and ask them to match the three that go together. (You may have the students do this in groups.) As a class, discuss the seven simple machines and other examples of each.
  2. Divide the class into groups of two to three students depending on the quantity of materials you have.
  3. Pass out the “Building a Catapult” instructions and worksheet, which asks students to design and construct a catapult, and to test it by using it to launch cotton balls. Go over the instructions with the class. Tell the students they have 25 minutes to build their catapults
  4. Give the students time to work. Once all groups are finished, make a starting mark. One at a time, ask the groups to come to the starting mark to launch their catapults. Allow each group to launch a cotton ball three times. Measure how far the cotton ball goes from the starting line each time. Have students record this distance and take the average of the three tries.
  5. Once all groups have launched their cotton balls, ask the students to create a graph of the average distances for all groups.
  6. Compare and contrast the different catapults and what simple machines are involved in each one.
  7. Homework: Have the students ask at least two people (parents, guardians, neighbors, other family members, etc.) what their careers are and what simple machines they use in their places of employment.
  8. During the next class period, make a chart on the board like this one:
    GearWheel and axleInclined planePulleyLeverScrewWedge
  9. Have students report what they learned from the homework assignment. Use the chart to list careers where each type of simple machine is used. If you did not assign the homework, or if some simple machines don’t have any careers listed under them, have the students brainstorm what careers might make use of each simple machine. Remind students that some careers will be listed under more than one simple machine. Some examples of careers that make use of each simple machine:
    • Gear — clock maker, bicycle designer
    • Wheel and axle — pit crew member, amusement park ride designer, automotive careers
    • Inclined plane — architect, roller coaster designer
    • Pulley — crane operator and/or builder, fishing boat attendant
    • Lever — hockey player, airplane pilot
    • Screw — construction worker, playground equipment designer
    • Wedge — rocket engineer, woodworker, ship designer
  10. Ask students to choose at least one career listed under each simple machine on the chart. (Make sure students choose a different career for each machine.) Have students use the internet to research information about those careers. A good place to send students for this research is the Bureau of Labor Statistics’ Occupational Outlook Handbook. You may have students work in pairs to complete this activity.
  11. After the students finish researching, have them discuss their findings as a class.


Optional resources for more information on the topics covered in this lesson

The Inventor’s Workshop
Leonardo da Vinci described and sketched ideas for many inventions using simple machines hundreds of years ahead of their time. At the Inventor’s Workshop, students can learn about simple machines and how Leonardo da Vinci’s sketches can be used as blueprints to perfect them.
Simple Machines
Students can learn further details about the six different types of simple machines.
Edheads Simple Machines Activities
Edheads’ interactive simulations cover simple and compound machines in the context of a house and a tool shed.
Dirtmeister: Simple Machines
On this interactive website, students can investigate simple machines and report on simple machines they see in the real world.

North Carolina curriculum alignment

Science (2005)

Grade 7

  • Goal 1: The learner will design and conduct investigations to demonstrate an understanding of scientific inquiry.
    • Objective 1.06: Use mathematics to gather, organize, and present quantitative data resulting from scientific investigations:
      • Measurement.
      • Analysis of data.
      • Graphing.
      • Prediction models.
  • Goal 6: The learner will conduct investigations, use models, simulations, and appropriate technologies and information systems to build an understanding of motion and forces.
    • Objective 6.02: Analyze simple machines for mechanical advantage and efficiency.

  • North Carolina Essential Standards
    • Science (2010)
      • Grade 7

        • 7.P.2 Understand forms of energy, energy transfer and transformation and conservation in mechanical systems. 7.P.2.1 Explain how kinetic and potential energy contribute to the mechanical energy of an object. 7.P.2.2 Explain how energy can be transformed from...