I learned about this museum on Southwest Airline's city guide for Charlotte. Firstly, you park next door to the museum. I had to go up to the 10th level for a spot but once I found one it was easy to park and a good size for my Toyota Tacoma.
The museum - I paid $7.xx for myself as a student.
There's a ten minute video that gives you the gist of their permanent exhibit. I appreciated the full sized walk throughs of a sharecropper's home, a front porch, living room, lunch counter, and bus.
I read EVERYTHING in museums. Literally: every. Single. Word. So with that said, I went through the first floor (permanent exhibits) in 2.5 hours. I read at a rate of ~200wpm.
I can't speak on the temporary exhibits because I didn't have the time to stay, but I'm very happy with the money I spent and all that I learned. Fantastic museum! I especially liked the end, you could pick a question to respond to and record it. Recordings of responses were played on a screen nearby. I recorded one myself.