Sound Wave
Light, Sound and Waves


Enrichment Activity for 5-11 11-14

What you need

  • Cardboard box
  • Pencil
  • String
  • Wet cloth


  1. Make a hole in a cardboard box.
  2. Tie some string round a pencil, and feed the string through the hole so the pencil is inside the box.
  3. Use a wet cloth to pull on the string.

Results and Explanation

The box amplifies the vibrations from the string as the cloth is pulled along it, making a sound that our ears can hear.

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.

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