Rubber-band the balloon to the straw, inflate, and set down. The expelled air will make it go!
How to Make a Balloon Car
What You'll Need
Toilet paper tube, balloon, 3 straws (2 cut to s ? ", 1 full-size), two wood skewers (cut to 4"), 4 peanut butter jar lids (or any large same-size plastic lid -- the larger the lid, the faster the car), pushpin, duct tape, rubber band, paint, paintbrush, scissors
1. Paint the tube; let dry.
2. To make the wheels and axle: Have an adult poke holes in centers of the four jar lids with a pushpin. The holes should fit a wood skewer snugly. Put the skewers through the short straw pieces and fit the wheels on each end of the skewer.
3. Use duct tape to attach straws (axles) to bottom of tube. The wheels should be about ? " from sides of tube.
4. Use a rubber band to attach a balloon to the end of a bendy straw. You should be able to blow through the straw to inflate balloon.
5. Tape the balloon and straw to top of car.
Originally published in the October 2013 issue of Parents magazine.