I haven't been but I would love to see the Steinhart Aquarium at the California Academy of Science in San Francisco. I think there's more than just an aquarium as well.
http://www.calacademy.org/academy/exhibits/aquarium/
They were able to lure Delbeek away from the Waikiki Aquarium to work there instead, anything that can pull a Canadian working at an aquarium in Hawaii has to be pretty impressive. Of course, I base that only on what it would be if it were me. Maybe the dude got tired of living in Hawaii. ("Oh! These mangoes are entirely too sweet. And don't get me started on the guava juice. And if I have to look at one more palm tree .... I swear I'll .....") ... Anyhow. I digress. Moving on.
San Fran strikes me a place you could probably spend a week just looking at things. I've never been. Need to change that. Well, not technically true, I have been, but just passing through on my way to Monterey Bay. In 2004 on a whim we just went to Monterey Bay because they had a great white shark on display. How cool is that!
Monterey Bay Aquarium in .. wouldn't you know it .. Monterey Bay, just south of San Fran, is IMO def worth a visit. Pretty area too. Pebble Beach golf course is nearby if you're into that sort of thing. We just drove by and said "Oh, so that's Pebble Beach golf course. How interesting").
In Long Beach (L.A. area) is the Long Beach Aquarium. Maybe the nicest aquarium I've ever been to. However it bears mentioning I haven't been there in a long time so maybe things have changed. I can't see it getting less nice, mind you.
Another thing I'd love to try one day is the Getty Museum (L.A. area).
La Brea Tar Pits are worth a visit if you're into dinosaur bones and stuff. Neat neat stuff. And the tar is still oozing out of the ground in places. And people think the oilsands are dirty.
Catalina ... oh, I would love to see Catalina. Jealous..
Are you guys driving down or flying in and then doing some driving? How much time do you have down there?