balloon car

The coolest car to play with is the one you make yourself!

The coolest car to play with is the one you make yourself!

While chemistry and engineering play an important role in the STEM field, there’s still so much more to master on your way to becoming the future face of medicine or the next astronaut to orbit the earth. Let’s play with some elements of STEM to propel a Styrofoam car — using just a little bit of air and a whole lot of physics!

Sir Isaac Newton developed the ideas behind modern physics and called them Newton’s Laws of Motion. This balloon-powered car experiment uses his third law, which states that every action must have an equal and opposite reaction. We see it at work here as the car zooms down our flat surface. Thanks to Newton and physics, experiments like this have never made STEM so fun…and fast.

Balloon Car

What You’ll Need:

  • Styrofoam trays
  • Bendy straws
  • Permanent marker
  • Scissors
  • Tape
  • Balloons
  • Straight pins


  • Cut a rectangular body out of the Styrofoam tray.
  • Cut out eight wheels. Make four of them the size of a quarter, and four of them double that size.
  • Tape the opening of the balloon around the short end of the straw so that no air can escape.
  • Next, tape the long end of the straw down the middle of the rectangle car piece. The open tip should be hanging out so that you can blow up the balloon later.
  • Push the straight pins through the center of the hubcaps and two wheels. Be sure to leave space between so that the wheels can spin.
  • Push the straight pin into the sides of the car to create wheels. Test pushing the car with your hand to make sure the wheels are able to spin. Otherwise, your car might not go very far.
  • Blow up the balloon through the straw, and then pinch the end so no air can escape. When you’re ready, unleash the power of your balloon-powered car, and let it race down the track!