Build

2-Wheel Balloon Car

Instructions

En EspaƱol
  • 1

    Here's what you need to make your 2-Wheel Balloon Car!

    • 1 balloon (9-inch or smaller)
    • 1 flexible straw
    • 1 wooden tongue depressor or craft stick
    • 1 straight straw
    • 2 candy mints (with a hole in the middle)
    • tape
    • rubber band (optional)

     

  • 2

    Make the jet

    Put the long end of a flexible straw into a balloon.

  • 3

    Make the jet (cont'd)

    Attach the straw and balloon so that no air can escape, using either a rubber band or tape.

  • 4

    Attach the jet

    • Tape the jet to the top of the tongue depressor or craft stick (i.e., the body).
    • Make sure the jet is as parallel to the floor or tabletop as possible. If it points up, down, or to the side, your car won’t move as fast or far as if the jet points straight back.
  • 5

    Make the axle and wheels

    • Slip two candy mints onto a straw.
    • Bend back the tips of the straw so the candy can’t fall off. Tape the tips in place.
  • 6

    Attach the body

    • Tape the axle to the bottom of the body, at the front. The end with the wheels is the front.
    • Make sure the wheels spin freely.
    • Make sure the wheels line up with the direction you want the car to move.

     

  • 7

     Power the jet

    • Blow up the balloon. Put your finger over the end of the straw to stop air from escaping.
    • Make sure the balloon doesn’t flop over onto the floor or tabletop. If it does, it will act like an anchor and will stop the car from moving.
    • Put the car on a smooth surface. Let go. ZOOM!

     

  • 8

    Did you know?

    Your balloon car uses jet power to move. The stored air in the balloon pushes through the straw, creating thrust—the force that pushes the car forward. So when air from the balloon moves in one direction, it pushes the car in the opposite direction.

  • 9

    Try this next!

    • Go for the record. How far can your car go? Try to double the distance by reducing friction (rubbing), lightening the car, pointing the jet back straighter, and straightening the axle.
    • Decorate and have a parade. Give your cars personalities by decorating them. Have a parade to show off all the balloon cars.