I am not sure how you classify Moody Gardens. There are a lot of things to do there. It certainly makes for a great day trip to Galveston. Moody Gardens has a 3D IMAX theater, there is an aquarium, a rainforest, a ride/film (simulated ride), etc. Each activity has a separate fee, but you can get discounted day passes. It is open every day around 10:00 AM, so you do not have to get up early to head down there as it is only a hour's drive from Houston. My kids loved the acquarium.
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