The Science Center is another great attraction in St. Louis. Admission is free but if you want to park close, you will have to pay.
The Science Center has several levels full of great attractions. My daughter loves to go there to see the dinosaurs on display and there are many exhibits where you can actually do an activity.
They also have an Omnimax theater (not free) that is a great experience. I have seen several movies there and its very life-like.
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