Cool colour-changing milk experiment

This colour-changing milk experiment is an activity that you can whip out on a rainy day to keep small ones away from the television.

This colour-changing milk experiment is an activity that you can whip out on a rainy day to keep small ones away from the television.

We're always trying (and failing) to convince kids that science is cool, so here's a little milk experiment which'll demonstrate just how fun science can be, in the comfort of your kitchen.

This simple experiment is glorious to watch and all the things you need are likely to already be in your fridge or cupboards.

And why does it make the milk move? The washing up liquid is an oil repellent so it pushes the fat in the milk, which causes the milk to move the colour around. It's like a fireworks display without the bangs!

Age group: 3+. Kids as young as three can take part in this experiment, you just need to check that little ones don't get any of the ingredients in their eyes.

Check out our other mind-boggling science experiments for kids here.

What you will need for this colour-changing milk experiment

  • A large plate (white if possible)
  • A cotton bud
  • Full fat milk (approx 100ml)
  • Food colouring
  • Washing up liquid

Step 1

Gather everything you're going to need for the experiment on a flat surface. Make sure you put a wipeable table cloth or some newspaper down in case of any spillages!

Step 2

Pour the milk onto the plate and add 2-3 drops of food colouring into the middle of the milk.

Step 3

Take a cotton bud and dip one end into washing up liquid.

Step 4

Place the tip with washing up liquid on into the centre of the milk and watch the display.

Step 5

Ta dah! Loads of fun and it hardly cost you a penny. Keep going until the milk stops moving. Pour it away down the sink and start again making sure the plate is clean and dry and free from soapy residue.

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