Its free to enter but they accept donations. We were 3 adults, 2 kids and donated $20 which was much cheaper than going to the zoo or other kids areas. The museum overall isn't very big in general but the layout they have makes it not feel cramped even with 50 kids. They have lockers to store your belongings, stroller parking and a small cafe. My only negatives are that parking can be hard to find depending on the day/time you go and there is no dedicated nursing area for mothers if needed. I personally don't mind finding a place to nurse but I do know some mothers would be more comfortable if there was some privacy.