Steel Straw Trick

In this science magic trick, an ordinary straw penetrates deeply into or through an apple or potato. All you have to do is thrust the apparently flimsy straw through the apple.

But how can a simple plastic straw—it may be examined before and after—become so rigid? The answer lies in a simple technique that takes advantage of air pressure and good aim. You'll know the trick but your friends won't be able to reproduce it easily.

  1. How to Do It
    Hold the straw in your dominant hand.
  2. Grasp it near the end so you can unobtrusively cap the end with your thumb and trap the air inside.
  3. Swiftly stab the apple or potato with the straw.

Why It Works
When the straw encounters the hard surface of the fruit or tuber, air gets trapped inside the straw. This stiffens the straw so it can pierce through the flesh. Once through, the air is released and the straw will be flexible again.