You will need:
- Festive cookie cutter
- Pipette (or teaspoon)
- Bicarbonate of soda
- Christmassy-coloured paint
- Place the cookie cutter on a plate. Spoon bicarbonate of soda into the shape, pressing each layer down as you go. Make sure you push plenty into the corners of your shape. You can use your teaspoon, the spoon handle or your fingers to press the bicarbonate of soda down.
- Smooth off the top of your shape. Don’t worry if your shape isn’t full to the top.
- Add some festive paint to your shape to make it look Christmassy!
- Use your pipette or a teaspoon to drip vinegar onto the shape. Watch it bubble and fizz! Continue to add vinegar to your shape. What does the vinegar do to the painted parts and the white parts? Which fizzes the most? Have you managed to make any really big bubbles?
- When you’ve had fun dripping vinegar onto your shape, see if you can lift off the cookie cutter. Your shape might be left behind or it might spread out. What colours has the paint gone – has it changed?