This is one of the best curricula for learning the 50 states and capitals I have found. A $30 value, it is available FREE at Homeschool Giveaways, but only for about 2 more days.
I had the opportunity to review Knowledge Quest's Globalmania some time ago, but I just didn't have time to fit it into the schedule at the time. It is a GREAT curriculum, and right now you can download it for FREE when you sign up for Knowledge Quest's newsletter!
Happy Mapping! :-)