A fun homeschooling field trip in Los Angeles is, of course, the Los Angeles Zoo.
We used to get an annual family membership, then go several times throughout the year. They have some nice exhibits now - habitats made more liveable to the animals. Which is a very good thing.
While I can recommend it as a fun homeschooling trip, I want to mention that a few years ago, the zoo promoted the fact that they had a monkey on Prozac. Apparently, the conditions were so bad that they had to drug this animal into contentment. I didn't renew our family membership after that, and we've only visited a few times since then. This was back when the Polar Bears hadn't had any shade for 30 years, either, and they changed that. Perhaps they aren't giving the animals dangerous psychiatric drugs anymore, either.
I should check into it!
Some links:
Why are Scientologists Opposed to Prozac?
Live and Grow: Welcome to Our Scientology Resource Library