Here's an additional contribution to the field trip thing; in honor of Lissa's move and because John and I spent four years of college and two years of married life in various parts of Southern California (I'm sure there are lots of people who have a much more thorough knowledge of the area - but you might as well start somewhere).
These were in fairly "lean" years, so these tend to be thrifty places to visit (or ones REALLY worth getting a season pass for). Never made it to Disneyland. We especially miss shopping at Trader Joe's. The Huntington and the Wild Animal Park are especially favorite places that we've returned to numerous times and always enjoyed.
Los Angeles Area:
Huntington Library, Gardens and Art Museums, San Marino, California
Lacy Park, San Marino, California
The J. Paul Getty Museum
Mission La Purissima Concepcion, Lompoc, California
Ronald Reagan Library, Simi Valley, California
San Diego Area:
San Diego Wild Animal Park, Escondido, California
San Diego Zoo
Mission San Juan Capistrano