Easy Air Pressure Experimets for Kids.

Easy Air Pressure Experiments for Kids.

Not feeling in the Lego building mood today? No problem, let’s do some cool backyard experiments and talk a little science. Today we're talking about air pressure. 

Lets look at air pressure in action with this cool drinking candle experiment.

Cool ha? Getting your kids to understand the principles of science when they are young is all about the foundations. Step one is collecting their ideas and dare I say the big word... Hypothesise. That really just means teaching your kids to think ahead and guess what will happen by tapping into what they already know. If you can ask them what they think will happen every time you do something cool together then your well on your way to setting up those foundations. So before starting, ask your child to guess what will happen, then write it down so you can reflect on it later.

The Experiment, You'll Need:

  • Water in a bowl.
  • Food dye.
  • Candle.
  • Lighter.
  • Glass.


  1. Add a small amount of water into a bowl.  Add some food dye if you’re feeling colourful.
  2. Pop the candle into the center of the water and light.
  3. Turn a glass upside-down over the candle.
  4. Watch what happens to the candle, flame and water.

So what's happening? What did you observe... Let’s look at the science.

Firstly. Air pressure. 

Air has a force that pushes on objects creating air pressure. When we capture some air in the glass and heat it up the warm air expands increasing the air pressure. Nature loves balance and tries to equal out the air pressure by allowing some of the air to escape the glass, creating the little bubbles you see. 

After the candle goes out, the air inside the glass cools down and the pressure outside the glass is higher. The balance is restored again with air being sucked into the glass bringing the water in the bowl.

Secondly. Combustion.

The candle burning is a combustion reaction. For the candle to stay alight inside the glass it needs a constant supply of oxygen. Because the air is limited inside the glass it quickly uses the available oxygen and that stops it burning.

Want to see air press in another cool experiment? Check this out.

Try it and let us know how you went. Happy Exploring!

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