What You Need:
- Tightly pinch both ends of a straw.
- Twist the straw like your winding up a kite string.
- Twist until you can’t twist any more. The untwisted portion of the straw will be hard because it is filled to capacity with air.
- Now, have your friend flick his finger at the air-filled portion of straw.
- The straw will make a loud popping noise!