How long would someone with little kids typically spend here?

I say you be 2 hrs easily. Especially if go out side

We go to the toddler area. 1-1.5 hours. Older kids about the same for the other stuff.

We usually spend 1-2 hours. There are some interactive exhibits and it depends on how engaged the kids gets. A really nice travelling Titanic exhibit starts in early June

We took are grandbabies and we where there around 3 hours, they really enjoyed being there

It is definitely a range as people have said. It is not hard to spend 1-2 hours. If your kids find something they are really involved in then it could take more, especially when there is a traveling exhibit.

I have a 8 and 5 yr old. My oldest loves going through the natural muesuem. There are three main parts inside. The special exhibits, which will have an extra charge if your not a member. The natural muesuem which covers the history and wildlife of central Texas, and the kids area. That has several different science rooms for the kids to explore as well as a "toddler town." If you do all three and cover them well it could easily take 2-3 hours. It all depends on how involved your kids are and how easily you can get them away.