We just went with our 6, 3 and 1.5 year olds and had a great time. They had a hands on dinosaur exhibit, an exhibit with local wildlife (crabs, etc.) including some live crabs and fish, and the kids room on the 3rd floor is worth the trip alone. It's got something for everyone (it says 6 and under on the door) and the parents can relax a bit while the kids play. They even have a baby area with a comfy chair for the parents with parenting magazines and a nursing chair with a boppy for parents. My only complaint was that it was not obvious to find the upstairs exhibits. Oh, and the gift shop doesn't have much MSC themed items, mostly space and dinosaur themed toys that you can probably get other places.
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