my 7 yr dd was chopsing away as usual at breakfast, sometimes stopping for breath, me wishing i was still in bed. the subject come round to rainbows and why no one had found the pot of gold. an apple and a lid from a painkiller tub helped to explain it. but trying to tell her about white light from the sun and how it splits into the different colours semi worked. any ideas how i can split the light, i remeember using a prism at school many moons ago, of course i havnt got one. how else can i split light without spending much money