Depends on your child's age(s). My kids are 4 and 7 and we were there for 2.5-3 hours
I'd say a good three to four hours taking your time and seeing everything
My kids are 6yrs and 18months, they stayed for about 3.5 hours. Both of them found couple things of there interest so they felt there should be more time for them to play but it was closing time.
We spent about an hour and a half there but my daughter is 9 so she wasnt interested in as many of the exhibits as she was when she was 5. When we took her when she was younger (in RI),it felt like we spent the whole day there while she played with every single thing they had!
I spent 2 hours there with my 2 year old daughter. Her favorite room was the water room so we spent a lot of time in there ❤
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