Preparation

For faster results ask technicians to add the raw ingredients to the cup with a stirrer. This allows students to simply stir and observe the changes.

Activity steps

1. Add 125ml PVA to the beaker.
2. Add 2 teaspoons of borax.
3. Mix with a stirrer.
4. The mixture can become firm and hard, like the texture of fat. If the mixture becomes too thick, add up to two table spoons of water. This will give the desired slime texture, which can be stirred and poured easily.
5. Add food colouring (optional).

• 125 ml PVA glue
• 2 teaspoons of Borax
• Cups or beakers to combine the mixture
• Food colouring (optional)
• Stirrers

Making slime is a great way to teach students about plastic science as it demonstrates the process of polymerisation before their eyes. It can also be used as a tool to promote critical thinking about plastics, which can be a polarised topic of discussion, especially in the media. Generally, longer chains of polymers are more difficult to recycle. Encourage students to consider this during the activity. Each year we produce three hundred million tons of plastic, which is a lot given that it is a relatively light material. Around half of this will be used just once before being disposed.