Just FYI for those of you going, there's a large group of zoos and aquariums nationwide that participate in this reciprocal membership program; I found out about it when I bought a membership to the Texas State Aquarium last week. Basically, when you buy a membership at one, you get free or discounted admission to all of them (and it's quite a list!) Definitely worth a look, the San Antonio Zoo and Aquarium are part of it (not Sea World, but Sea World is overcrowded and overrated IMO).

http://www.sazoo-aq.org/support/file...Reciprocal.pdf