Ages: 3-5
Less than 30 minutes
Grownup needed
What makes a tissue paper caterpillar wiggle and suddenly grow? Let's explore the magical phenomenon of capillary action.
Lay the tissue paper flat on the table as shown, and draw horizontal lines on it using your favourite coloured markers.
Place the tissue paper horizontally and apply PVA glue along the top edge as shown. Then use the wooden stick to roll up the tissue paper and secure it.
Stand the wooden stick with the tissue paper upright, and press the tissue paper down towards the table to create wrinkles. Then remove the tissue roll - this will be the caterpillar's body.
Use markers to draw eyes on one end of the caterpillar.
Place the caterpillar on the plate. Use the dropper to collect water, then start dropping water from the caterpillar's tail. Now watch your caterpillar come to life!
Tissue paper contains many tiny plant fibres and is highly absorbent. When water is dropped onto the compressed tissue paper, it quickly absorbs the water through capillary action. The wet fibres expand and try to return to their original shape, making it look like the caterpillar is growing.