How long does it take to walk through?

This is easily a one hour tour, and could be quicker, depending on what you want to see.

I would say 45 minutes to 1 hour depending on the crowd and how much you stop at each exhibit.

We have taken up to an hour and then stayed in the end section creating creatures for another 20 minutes. We have also flown through in 20 minutes too. We had annual passes for several years. The more activities/presentations you stop and listen to or participate in the longer it will take.

With a toddler id say 30-45 depending of course on how long you stop at the touch pool and what not.

I'd say about an hour depending on the age of your kids

I agree that 45 minutes to an hour or so good time allotment. Depending on the age of kids.