We've been members of the Children's Museum for several years now, partially because it provides a great activity for the kids to do during the long cold winters.
Our kids have grown up with the museum so we've diverted our focus over the years. In the beginning, we would spend a lot of time in the 'nursery" room on the second floor and the "water" room on the third floor. As they grew older, we would spend more time in rooms such as the "workshop" or see what the rotating exhibit was (they tend to rotate once per quarter). So, the idea is that if you have differently aged kids, you're likely to find SOMETHING that will appeal to their interest.
I think the interest starts to wane around age eight or nine. Those kids tend to be in the studio room where they can paint or draw while their younger siblings are off exploring other areas of the museum.
The only thing I don't care for at the museum is that it can take them awhile to fix things that break. A long while. As in several years. Eventually, a capital improvement will upgrade the entire room at once and everything works again (I'm looking at you, nursery room), but routine maintenance would work wonders in ensuring that the kids can play with everything for every visit.
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