Balloon Rocket Science Experiment for Kids

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Looking for a hands-on science experiment that’s simple, exciting, and packed with learning? Try this Balloon Rocket Science Experiment—a classic STEM experiment that kids love, and a perfect way to explore motion, force, and energy.

This balloon experiment is one we have done many times over the years and I am excited to refresh this old classic for all of you!

What You’ll Need for the Balloon Rocket:

A long piece of string, yarn, or fishing line
A paper or plastic straw
A balloon (round or long)
Tape
Two chairs or anchor points

Instructions to Set Up the Balloon Rocket

Step 1: Thread the Straw

Take a long piece of string and thread it through a straw. This will act as your rocket’s track.

Step 2: Anchor the String

Tie each end of the string to a sturdy object like a chair, railing, or doorknob. If one end is higher than the other it will help with speed and motion.

Step 3: Inflate the Balloon

Blow up a balloon but don’t tie it off. Hold the end closed or clip it with a clothespin or binder clip. The amount of air in the balloon will change the thrust or force at which the balloon travels.

Step 4: Tape the Balloon to the Straw

Attach the inflated balloon to the straw with tape. IT helps to get your pieces of tape ready in advance. The balloon should lie horizontally along the straw. It is nice to have a helper for this step!

Step 5: Launch!

Just for fun, you can do a count down to blast off like a real rocket! Let go of the balloon and watch it rocket across the string. The escaping air will propel it forward like a jet engine.

Watch it Go!

The Science Behind the Balloon Rocket: Newton’s Third Law

This activity is a simple and visual demonstration of Newton’s 3rd Law of Motion: For every action, there is an equal and opposite reaction.

The action: Air rushing out of the balloon.
The reaction: The balloon being pushed in the opposite direction along the string.

It’s a great way to explore basic physics principles in a way that kids can see, feel, and understand.

Real-World Applications of This Concept

The same principles behind the balloon rocket apply to many technologies we use every day:

Jet Engines – Just like the balloon pushes air out to move forward, jet engines expel exhaust to propel airplanes.
Rockets and Spacecraft – Rockets burn fuel and force gas out of the engines, which pushes the spacecraft in the opposite direction.
Fire Extinguishers (CO₂) – Pressurized air/gas is released rapidly in one direction to push out extinguishing material in the other.
Sprinklers – Some rotating sprinklers spin because of Newton’s Third Law—the water being sprayed in one direction spins the device in the opposite direction.
Thrusters on Boats or Submarines – Controlled jets of water or air can change direction or speed.

Helping kids connect simple experiments to real-world uses builds excitement for engineering and technology careers!

Ways to Extend the Balloon Rocket Experiment

1. Try Different Balloons

Compare short round balloons to long skinny ones. Or even multiple balloons taped together! Which one travels farther or faster?

2. Change the Angle or Length

Adjust the height of your string to explore how slope impacts speed. Try different lengths of string.

3. Add a Payload

Can your rocket carry a LEGO minifigure or a paperclip passenger?

4. Make it a Race

Set up two lines and race different balloons to see which design works best.

5. STEM Challenge Journal

Have kids record their predictions, observations, and conclusions in a science journal.

STEM & Learning Concepts Explored

This experiment can be used to teach or review the following:

Force and Motion
Air Pressure
Newton’s Third Law of Motion
Design and Engineering Process
Cause & Effect

Classroom or Group Use

This makes a fantastic classroom demo or small group STEM center. Provide kids with different materials and challenge them to build the fastest balloon rocket possible.

Why We Loved This Experiment

This balloon rocket was a HUGE hit at our house! My kids tried several different balloon shapes, created paperclip riders, and tested who could build the fastest rocket. It’s quick to set up, budget-friendly, and full of discovery.

Want more physics fun? Check out our:

Give the Balloon Rocket Science Experiment a try—you’ll be amazed at how much learning can take flight with just a balloon and some string!

Also find it on YouTube:

Balloon Rocket Science Experiment for Kids

What You’ll Need for the Balloon Rocket: