Cook the tapioca pearls according to packet instructions. Once cooked, allow to cool
Make up the jellies using half the amount of water stated on the packet (so that the jelly is firmer and will turn out of the dish successfully)
Lightly oil the dishes or moulds. Place some of the tapioca balls and jelly worms or spiders in the bottom of the dish and pour on just enough jelly to cover them. Chill until set before pouring on more layers of jelly, leaving each layer to set before adding the next one - you can make different colour layers by using different flavour jellies and alternating them in the dishes.