Magic Rainbow Milk

Magic rainbow milk: a simple science experiment to delight kids!

At Mud Mates HQ, we are big fans of messy play. My kids just love getting messy, and of course it provides such a great opportunity to learn.

However….. I’m all for quick and easy, and to be honest, sometimes not TOO much mess. With little ones like Miss 2, attention spans can be short, so I’m not keen to spend ages setting something up only for it to last five minutes.

So when a friend introduced me to Magic Rainbow Milk, I knew it was right up my alley. And I was right – it’s cheap, quick, and seriously cool. Miss 2 thought it was pretty amazing too!

Even better? If you set it up outside (highly recommended), there’s not much mess to clean up afterwards.

What You’ll Need

• Milk – full fat not skim
• Shallow dish or bowl
• Food colouring
• Dishwashing liquid (in a small bowl)
• Cotton buds

Optional (for extending the activity):

• Baking soda
• Vinegar
• A dropper, teaspoon, or small cup
• Straw

How to Do the Magic Rainbow Milk Experiment

1. Pour a thin layer of milk into your shallow dish.
2. Add a few drops of food colouring to the surface – one colour or a mix.
3. Dip a cotton bud into the dishwashing liquid.
4. Gently touch the milk with the soapy end of the cotton bud – right in the middle of a colour drop.
5. Watch the colours swirl and burst like magic!

Miss 2 was mesmerised. We kept going until the colours turned into “muddy milk,” then emptied it and started all over again… and again!

Extend the Fun with Foaming, Bubbling Rainbow Milk

When Miss 2 started to lose interest, I grabbed the baking soda and vinegar to keep things going.

• Sprinkle (or dump, in our case) baking soda over the milk.
• Add vinegar using a dropper, spoon, or pour straight from a cup.
• Watch the mixture foam, bubble, and fizz!

And for a final twist – hand them a straw and let them blow bubbles into the coloured milk. So simple, but so much fun.

Try It Yourself

If you haven’t done this activity before – give it a go! It’s super easy and always a hit with kids of all ages.

Want more easy, fun ideas like this?
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