Scavenger Hunt in Chicago with friends?

this summer, my friends and I wanna go to Chicago and do a little scavenger hunt. Hah, so we don't wanna do anything illegal, that can get us arrested, like defacing stuff ya know. But we just wanna have some fun, we're all girls, just by the way. THe hunt is pretty much photo based, so the things i have already are like, Casually walk through someone's photo, take a picture with a living animal, get someone's phone number, and stuff like that. Anyone have any more legal...but fun stuff to do in CHICAGO?