Years ago, my older son and I raced balloon rockets across our living room. This year, for summer science camp we took our balloon rocket making supplies over to a friend's apartment to try outdoors with the kids. As you can imagine, a balloon rocket experiment was lots of fun for active kids who like some WOW! in their activities.

While the kids played by themselves, the moms set up the course. If you have mostly older kids they can do this all by themselves. Our mix of kids were mostly younger. Plus, we wanted to chat!
How to Make Balloon Rockets
This is a great STEM project for kids that teaches kids about force, propulsion, friction, and Newton’s third law of motion (that for every action in nature there is an equal and opposite reaction). As you know we love STEM based play dates!
What you need:
- Balloons
- String
- Scissors
- Straws
- Tape
- DIY science campers
Instructions:
Extend the length of string as far as you can, given the limitations of your space. Tie one end securely (we tied it on the fence). Thread one straw through each string and tie up the other end. Slide the straw all the way to one end of the string.
Blow up a balloon. Without letting the air out, carefully tape the balloon to the straw. Clasping the neck of the balloon tightly, count to 3. Let go! Watch your balloon whizz down the course!!
As you can imagine, with two 5 year olds, a 9 year old and a 3 year old, it was difficult (actually impossible for us) to get all the balloons ready to go at the same time, so we didn't have so much as a race as a free-for-all.
MORE: How to Make Indoor Paper Boomerangs
My 9-year-old was the only one who could remotely focus on the science behind the balloon rocket experiment. I asked him why the rockets go so quickly and he correctly responded that the energy escaping air creates a forward moving force. He and I were also able to compare the speed of a small balloon with a large balloon.
Variations:
- Compare the speed and distance of differently shaped balloons.
- What happens if you use a shorter straw?
- We used thin straws. What happens if you use a straw with a wider opening?
- Compare different types of string. You could use twine, yarn, thread... etc.
- Tie strings on an upward slope, a downward slope and flat. What's the difference in speed?
After the boys lost interest in the the balloon rockets, the 3 year old was quite entertained when I simply blew up a balloon and let it go. No need for the straw and string for her!
MORE: Use those left over balloons to blow up a balloon with science, make balloon yo-yos or play balloon tennis!
This is a super easy science experiment with so much entertainment value. I highly recommend it. It's also a great activity to do indoors on a rainy day.
MaryAnne @ mama smiles says
This is one of y favorite science activities - simple and fun!
Erica MomandKiddo says
Simple and fun! That's exactly what Megan and I are going for with our summer camp!
writersideup says
Oh, Erica, I LOVE this! I can imagine kids having a blast with this! In fact, a few years back I wrote a scene in a novel (which is now shelved forever--the novel, not the scene) that included something very similar, only with water 🙂
Erica MomandKiddo says
With water!! My boys would love that. Maybe even more than the balloons!
Erica Becka says
Our living room resembles a giant spider web!! lol. This activity was super fun!!
Thanks again!!
Erica says
How fun!