Moody Gardens is a fun place for people of all ages -- if you go during the right time of the year. As far as when the right time is, who knows? They remove exhibits at a whim and replace it with nothing; sometimes leaving an entire exhibit bare and boring.
The aquarium is really neat, but it's way over-priced for what you get to see.
The boat is very boring. You literally get to see a bunch of junky water and there's absolutely no entertainment. Could be romantic at night, but not for kids at any time.
If you have discount tickets, I recommend Moody Gardens. If you don't, save your money.
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