Cool colour-changing milk experiment

We’re always trying (and failing) to convince kids that science is cool, so here’s a little trick 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.

What you will need

  • A large plate (white if possible)

  • A cotton bud
  • Full fat milk (approx 100ml)
  • Food colouring
  • Washing up liquid