Blast Off Air Pressure Experiment

Materials Needed:

Squeeze bottles (Similar to the type you can purchase at a dollar store for ketchup and mustard.)
Rocket ship stickers
String (Experiment with different lengths to see which works best for you.)
Scissors

What To Do:

Remove all the caps from the squeeze bottles.
Tie a knot in one end of the string.
Thread unknotted end of string through cap and tie it in a knot.
Pull string back to cap and place the loose string into the bottle.
Place cap on bottle.
Stick rocket ship stickers on the visible knot, on the outside of the cap.
Have the children take turns squeezing the bottles and watching the rockets blast off.