3 and up. I just went a few months ago and my granddaughter was 3 and I paid for her but not my grandsons that were 2 and 2 months
Says 3 and under are free, kids are considered 3-12, and adults 13+
We just recently took our 2 year old. In our case, he wasn't quite into yet, but we did notice him engaging with a few of the exhibits, and he REALLY liked the toddler play area on the second floor. In our case we'll probably aim for 4 (or close to it) before giving it another try, although I can also imagine other kids appreciating it as early as 2. Hope that helps!
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