I think so far there are three of us in this committee...
Anyway,
The prizes need to be divisible by whatever number the [logistics committee?] decide will be the number of the groups, so third prize will probably end up being a small bag of lollies for each person?
We could get some of those crappy yet awesome medals that I remember getting in primary school at athletics carnivals and stuff, you know, those little plastic ones with a colourful ribbon...
Any other ideas?