I've just had a shot at playing a super charming online game called THINGDOM at the Science Museum website (UK based). I learned of it via this week's edition of the BBC's ClickOnline feature WEBSCAPE, anchored by the ever-resourceful, tireless and always user-friendly Kate Russell (I'm convinced that she is at least PARTLY electronic -- and I mean that in the best possible way).
THINGDOM is aimed at children, and is a very cute, easy-to-play game to teach the principles of genetics. Go on! Play it. Make things. And help them make even more things.