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Science Rocks!

Tennis Ball Lift


your results

Sent in by:
Heather of Charlton, MA

Look Ma, no hands! Invent a Tennis Ball Lifting Contraption.

Materials Needed

  • tennis ball
  • 2 plastic cups
  • 2 feet of string
  • broomstick
  • 50 pennies
  • tape
  • scissors
  • table
  • meter stick



  1. Use two cups, string, scissors, tape, a broomstick, a table, and up to fifty pennies to create something that will allow you to lift a tennis ball 50 centimeters into the air without using your hands.

What did you build? How many pennies did you use? Did your invention do the job? Why do you think it worked or didn't work? Experiment with other types of balls and different coins. Share your experimental thoughts with ZOOMers around the world by sending them in to the ZOOMsci feedback area on the site.

Some of your Results

Michelle, age 9 of New York City, NY wrote:
It lifted up very high and I didn't think that it would work.

Carly, age 9 of Oconomowoc, WI wrote:
It lifted higher than 50 centimeters.

Brenda, age 11 of Yonkers, NY wrote:
At first I really didnt think that it was going to work so I didnt use all the meterials but withot 2 meterials guess what? It worked I was truly amazed.

Emily, age 8 of South Charleston, OH wrote:
Well I made sort of like a scale. I put the tennis ball on one side and the pnnies on the other. It worked but it took me awhile to find out how to do it.

Faith, age 8 of South San Francisco wrote:
I used strong tape to attach string and the tennis ball and then I made something like a pully and used my feet to pull!

Anna, age 5 of Schererville, IN wrote:
IT works... cool! My Dad and I built it with two cups, a broomstick and a rubber ball with tape. The coins raised the ball off the ground!

Julie & Kacie of Warrenton, VA wrote:
We didn't use tennis balls, but we used something that is about the same weight. We used 22 pennies. We made by placing the broomstick on the table. Then we put the cups on the string, and draped that over the broomstick. Then we dropped the pennies into the empty cup, so it acted as a pully.

Julie, age 12 of Bronx, NY wrote:
I held the broomstick with the sweeping part sticking up, and I put the rope over the broom and stuck a hole throught the bottom of the cup to stick the rope into and made a not. Then, I put the pennies in one cup with tape over it and one with the tennis ball and tape over that cup. The rope worked as a pulley and lifted 51 feet.

John, age 15 of New York City, NY wrote:
I gave up, it was too hard!!! It took me 5 hours to realize that it was impossible!!!

Katie, age 11 of East Hartford, CT wrote:
I did it only using tape, cups and a stick.

Tori, age 10 of Waverly, IA wrote:
We did the 'Tennis Ball Lift', but we used a balloon! It was so awesome! It went really high! Try it! You'll find it neat!

not yet implemented