Fred Jones Museum is on the University of Oklahoma campus. It's not just for the campus community but for the entire city. They received the most important French Impressionism collection a few years ago. It is a wonderful exhibit - Weitzenhoffer Collection which offers Van Gogh, Monet, Renoir and other well known artists.
Admission is around $5 for adults and I know they give a discount for children of a certain age and seniors. Parking is limited close to the museum but there is more parking near by.
PROS: Beautiful and Elegant Museum
CONS: Parking
more