Properties of Matter

Indestructible Bag

Enrichment Activity for 5-11 11-14

What you need

  • Water
  • Clear plastic watertight bag (e.g. watertight, resealable food bag)
  • Some pencils


  1. Fill the plastic bag with water
  2. Push a pencil through the bag
  3. Then another... and another

Results and Explanation

The bag doesn't burst because the plastic stretches rather than tears as the pencils are pushed through it. If you take a pencil out you can plug the leak simply by putting it back through the holes.

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