Yes, a three year old could have lots of fun. Lots of hands on activities.
Yes, lots to do!
Yes. Hands on inside and outside. Nice weather helps.
Yes. My 2 and 4 year olds loved it!
There's stuff which will appeal to most three-year-olds, for sure. However, the target is more six-to-early-teens; they (and grownups who still have a sense of curiosity) will get the most out of it. Put another way, your preschooler may get bored before older kids are ready to leave.
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