Fizzy volcano
Pour vinegar on baking soda and watch the lava bubble up.
You'll need
- Baking soda
- Vinegar
- A small cup in a tray
- Food colouring (optional)
How to play
- Put the cup in the tray and add two spoons of baking soda.
- Add a drop of food colouring.
- Pour in vinegar and step back.
- Try different amounts and compare.
Try saying this
“What do you think will happen when it meets the vinegar?”
Your part
Pour with them and gasp when it fizzes. Wonder aloud, ‘Why do you think it grew?’, and keep eyes clear of the foam.
If it stalls
- Watch the fizz first, then ask what they would change.
- Do a smaller test in a spoon if the big one feels too much.
Short on time? One spoon of baking soda and a splash of vinegar.
Why it's good for them: Mixing and watching a reaction teaches children to predict and test.
Not this one? Try sink or float, ice rescue, walking water rainbow.