I had been to this museum over ten years ago. Not much has changed. Some interesting exhibits on Oak Ridge's past. (Oak Ridge still has a bit of a spooky feel to it. While the city itself is nice and modern, as you travel the countryside around the the city limits you just wonder how much of the area's legacy is still buried throughout the hills.)
As for the rest of the museum there is a lot of interactive science exhibits for kids. This is probably the best part of the museum. There is also a small gift shop and an auditorium where they show movies and/or do demonstrations.
A good place to spend a couple hours on a rainy day. Otherwise, head to the Smokies south of Knoxville.