One children's(*) game is to get two maps at different scales. Pick a random location on one, write down its grid reference, then find the same grid reference on the other. Hours of fun. (In the UK we have marvellous Ordnance Survey maps with a standard grid; I presume the US has an equivalent.)

http://xkcd.com/201/ describes another game.

-----
(*) - OK, I've not actually seen children playing this. Or anyone other than me.