This sounds kind of lame because this place is famous for 90210 but this school seems like a great place to shoot if you're into architecture. They have beautiful buildings dating back to the early 1900s, which I guess is considered old for cali. Try going in the late afternoon.

I really enjoy taking close-ups of the big garden at the Getty Center.

The buildings of Continental Park -- especially the courtyards inside them -- make for wonderful backdrops for photos!

Old Spanish Architecture located right at the beach

(Have to plug my alma mater.) The campus is really beautiful, not crowded, and as long as you wear a "I <3 Nerds" t-shirt, no-one will bother you. (Actually, that might attract too many guys...)

And, it's right in the heart of Pasadena, so you can go to old-town afterwards.

[Also in Pasadena, about a mile from Caltech.] The gardens are really pretty, and there is also a museum. (Not sure if you can take pictures everywhere inside, though.)

it's got interesting architecture, a beautiful fountain and is near the Neighborhood Church so you could photograph both sites on the same day

You can probably find nice spots at this park. Good luck!

Huge campus filled with old beautiful architecture. Some of the buildings look run down, which I think will only add to the photos. You should check out the Wadsworth Theater.