No visit to San Antonio is complete without a trip to the Alamo, especially if you like history!
You can easily walk from the alamo to the riverwalk, so you can easily do both of these in the same trip.
Right next to the zoo, you can walk from one to the other. And the tea gardens are free :)
Caves for you to explore!
One of Texas's favorite summer activities is floating the river. New Braunfels is just a short trip away, where you can have water access. There are multiple companies that offer float rentals for your trip down the river, this is just one that we've done in the past and can recommend.
This is a restaurant, where the workers dress up as characters from books, tv shows, etc. I've been once ,and our waiter was Shaggy from Scooby Doo. It's also kid friendly!