Properties of Matter

Straw Water Gun

At home for 11-14 14-16

M&M - Straw Water Gun

What you need

  • A drinking straw
  • A friend
  • A ruler
  • Scissors
  • Sticky tape
  • Saucer of water


  1. The challenge is to lift the water from the saucer using a straw but without sucking
  2. Get your ruler and cut your drinking straw into two pieces: one 3cm long and one 5cm long
  3. Join the pieces together with sticky tape along one side so they form a 90 degree angle, but leave both ends open
  4. Stand the smaller end of the straw in the saucer of water
  5. Now blow hard!

Results and Explanation

When air moves, its pressure falls. So when you blow, the pressure at the top of the straw drops. But the air over the saucer keeps the same pressure, so the water is pushed up the straw.

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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