• PVA glue

• Bicarbonate soda

• Contact lens solution, “buffered” (key ingredient: boric acid, can use eye wash instead)

• Food colouring (red, blue and yellow)

• Glitter (optional)

• Baby oil (optional)

• 3 mixing bowls

• Spoons

• Measuring cups and spoons

• Muffin tray (for storing your slime blobs)

Make sure you are working on a wipe-clean surface, and wearing messy clothes or an old apron!

Measure out 250 ml (1 cup) PVA glue into a bowl.

Add 1 tsp bicarb and mix together.

Divide the base mix into 3 equal parts. Each one will be used for a different primary colour: yellow, blue and red.

Choose one of the primary colours and add a few drops of food colouring to the mixture, making sure the colour is nice and vibrant.

Next, do the same for the other two mixtures.

Add some glitter to each of the three colours, matching the glitter to the colour of the slime.

This will help later when you want to remember which colours you added together to get the secondary colour you end up with!

Add a little baby oil – it helps to keep the slime stretchy and stops it from sticking to your hands (optional). 

Add contact lens solution by squirting in and mixing together.

You’ll probably need a few tablespoons for each colour mixture.

The mixture will come together and start to stick to itself instead of the bowl as you stir.

Add a bit more solution until it makes a big lump in the bowl.

Add bit by bit, stirring in the meantime, to make sure it doesn’t make your mixture too solid.

Depending what brand you use, you may need a little more or less contact solution.

Add a few more drops of baby oil, take the slime out of the bowl and keep kneading it and playing with it.

If it sticks to your hands, add a little more contact lens solution and knead into slime. It should stick together like very squidgy dough, and not stick to your hands.

If you don’t want to directly touch the slime, try putting it into a clear plastic bag and handling it through the bag.

Break up each of your primary coloured slimes – blue, yellow and red – into three parts and use the muffin tray to keep them separate.

Try mixing red and yellow, red and blue, or blue and yellow.

Which two colours made the new colour you have?

Pull the slime apart in your hands and have a close look at the glitter to remind yourself!

Once you have had a go at making all the different secondary colours, play with your slime!