There are some fine things to do already mentioned. But I think that, for a college student, you'd find more amusement along Haight Street - Ashbury to Stanyan or Telegraph Avenue in Berkeley (a short BART ride). Chinatown (San Francisco or Oakland) can be fun. If you want more active stuff, The Exploratorium at the Palace of Fine Arts in SF of Lawrence Hall of Science (above UC Berkeley campus) are science-oriented play.