Science Experiment for Kids: Balloon Rocket

by Holly Homer on March 20th, 2011 | 1 Comment »

I think I have always wanted to be an astronaut. Maybe since birth. The sky is such a big place begging to be explored....and the space suits are pretty cool. After taking college calculus, it was apparent that anything with heavy math wasn't my strength. Oh, and I get dizzy with any spinning motion. Maybe I am not cut out for space exploration, but maybe one of my kids will decide to pick up the dropped family legacy. My boys are fascinated by all things outer space (even if it doesn't directly relate to Star Wars). The last shuttle launch was a much anticipated event at my house.

Today's experiment takes the excitement of launches into our backyard. We will be creating NASA with fishing line, straws and balloons. Just like Apollo 13 only without the danger. So grab some supplies from your kitchen junk drawer and join us in making a Two-Stage Rocket from the book, Totally Irresponsible Science by Sean Connolly.

Science Experiment Using Balloons

Materials

drinking straw cut into 1 inch pieces
fishing line
two trees/or something in your backyard to anchor the fishing line 100 feet apart
plastic bottle
two long balloons
tape

Directions

String your fishing line between two objects in your backyard 80 to 100 feet apart. Before you attach the second end, thread the fishing line through two of the straw pieces so they can slide on the line.

Take the water bottle and cut off each end so that you are left with a 3-4 inch ring. Tape this ring onto one of the straw segments.

Please learn from my mistake. When I went to the store for "long balloons" I bought the ones that are for making balloon animals. When I got home I realized that those are impossible to blow up without a pump of some sort. So, from here on out, I am showing you how to do this with round balloons which won't be nearly as effective as traditional long balloons or inflated balloon animal ones!

Blow up one balloon and then hold it in the ring not letting the air escape while you put a second balloon in place. If done with the right balloons and better coordination, the second can be positioned so that it stops the air escape from the first.

Release the second balloon.

Whoooosh!

The second balloon propels the rocket forward and then as it gets smaller, the first balloon takes over.

Stage one! Stage two!

We repeated this over and over with just one balloon because it was easier for me...

...and I had a very willing audience.

Why does this happen? "For every action, there is an equal and opposite reaction." This principle observed by Newton, lies at the heart of rocket (in this case, balloon) science.

Here are the full instructions for this science experiment for kids:

Publicity-Mad Science Club Experiments 4

This is the fourth fun and easy science experiment that you can do with your kids at home. The following are the other experiments within this series:

The entire series was inspired by the people at Workman. They publish an array of crazy cool children’s science resources. What I love about this series of science books for children is that they are extremely accessible. The directions are simple and most of the supplies you probably already have at home. I love the look on my 5 year olds face as he chases a rocket we just made through our backyard.

When Holly isn't dreaming of being an astronaut or building balloon rockets in her backyard, she is writing. She is the stay at home mom of three boys. She is a Dallas Area Blogger who writes June Cleaver Nirvana and is the editor of She is Dallas. She can be found on Facebook and Twitter.