Launching Your Own Mini Rocket

Using a balloon, string, and some tape, you can make your own balloon rocket! This fun experiment shows how action and reaction forces work.

1. Thread a long string through a straw and tie the string between two chairs.
2. Blow up a balloon (don’t tie it), tape it to the straw, and let it go.
3. Watch the balloon zoom along the string as air rushes out!

What’s Happening?

The air leaving the balloon pushes in one direction, and the balloon moves in the opposite direction—just like a real rocket!