i stayed in oregon as an exchange student last year.
Take him to parties. Even though he's probably used to better/different parties he'll most likely like it. I know i did!
And just take him with you when you do everyday fun stuff like swimmming in the river, boating, mudding/offroad driving, dirtbiking. Pretty much all the fun stuff you do, he'll probably enjoy too. Trust me, he doesn't want to see tourist stuff. ANd if he does, send him home (not really). Thats what vacations are for.