Can anyone suggest some simple experiments to do with water for a 4 year old?

[JuniperTisane]

DS1's topic at preschool is water this term. He's very motivated by experimenting and I've run out of ideas to try indoors at home. We've done freezing and melting, freezing hot versus cold water, pouring into different size containers, food colouring and bubble play. What else could we do thats sort of investigative rather than just playing?

[rosiecg]

Look at what floats/sinks? Mix different materials (sand, oil, dyes, gravel, mud etc) with the water and see how it changes?

[NannyNim]

Raisins in carbonated water/lemonade is brilliant fun!

Putting one hand in cold water and one in hot for a short while then putting them both in warm water has a strange effect. That's more to do with the senses I suppose but it's interesting.

Boiling to create steam as well as evaporating and condensing? Link it to the weather cycle then you can collect rainwater and watch it evaporate or maybe even freeze!

[chocomochi]

Adding bicarbonate of soda to carbonated water is good fun. Mixing flour in water gradually to turn it solid.

[mausmaus]

add cornflour
makes a weird solid/liquid slime

[Parietal]

freeze small amount of intense food colouring (e.g. drop of red). drop into big tub of warm water that appears still. you should see the colour spread slowly across the tub in interesting patterns.

[SunnySomer]

Try pouring through different materials (different fabrics, papers, plastic bag etc) to see what is and isn't waterproof. Get him to predict his answers first, then test them.

[JuniperTisane]

Oh just come back and found this thread! Great ideas, thanks everyone.