- Label the two squirty bottles A and B
- Remove the lids from both bottles
- Add bicarbonate of soda to bottle A until it is one-third full
- Add cornflower to bottle A until another third is full - the bottle should now be two-thirds full
- Add a few drops of food colouring to bottle A
- Fill the remainder of bottle A with water
- Fill bottle B with white vinegar
- Add a few drops of food colouring to bottle B
- Securely replace the lids on bottles A and B and shake hard!
- Squeeze bottle A to draw a picture on the ground
- Trace the picture with bottle B to see the fizzy chemical reaction!
- Use your squirty chalk outside - a flat even surface works best
- The squirty chalk can be easily washed away with water
- Wear clothes you don't mind getting messy
- Try using different food colourings in each bottle for a rainbow of fun!