top of page

Muscular System

With this experiment kids learn how muscles and bones move our arms by using cardboard tubes, balloons and pipe cleaners. 

Finished model of the muscular system!

Lesson plan: In today’s activity, we will see how our muscles move our arms.

Materials needed:

  • 3 cardboard tubes, 1 long and 2 short

  • 2 long skinny balloons

  • 2 Pipe cleaners, 1 long and 1 cut in half

  • Sharpie


  1. Using the sharpie, label the long cardboard tube as “Humerus''. Using a hole puncher, you need to make holes on one end of the “Humerus” tube. They should be in one parallel line but on opposite sides of the tube, so when you string the pipe cleaner, it should come out the other end. 

  2. Label one small cardboard tube as “Radius” and the other as “Ulna” and make two holes with the help of hole puncher on one end of the tubes, same as you have done on “Humerus” cardboard tube.

  3. Take your skinny balloons and inflate air to ¼ of the length of the balloon. Tie a twist knot on the open end. Now squeezing the balloon with your hands, bring all the air in the middle part of the balloon. 

  4. Label one balloon as “Bicep” and the other as “Tricep”

  5. Tie both ends of the “Tricep” balloon to the ends of the “Humerus”(long) cardboard tube using a double knot.  

  6. Lay down all your cardboard tubes on a table in a “Y” shape. “Humerus” tube on one end and “Radius” and “Ulna” tubes on the other end. Aling all the holes in the same line, so you can string the pipe cleaner through the holes on the cardboard tube. The “Humerus” tube should be in the middle of the “Radius” and “Ulna” tubes. Twist pipe cleaners on each end to secure.

  7. Hold the open ends of “Radius” and “Ulna” together and using a hole puncher, hole punch the ends. Take the smaller piece of pipe cleaner. String it through the holes on the “Radius” and “Ulna” tubes. Twist the ends to secure. 

  8. Tie one end of the “Bicep” balloon where the “Radius” and “Ulna” tubes meet. Tie the other end of the balloon a little under where the top of the “Tricep”balloon is tied. 

  9. Your “Muscular System” model is ready. It should be able to stay in an upright position with “Radius” and “Ulna” as the base and “Humerus” as the top. 

  10. This models the entire arm movement of “contraction and extension” as you hold the  “Radius” and “Ulna” down and pull the “Humerus” tube back and forth. Notice, as you pull and release how the “Radius” and “Ulna” muscles stretch and bulge up. You can try doing the same movements of your arm as you expand and contract at the elbow joint.​


bottom of page