I give the kids a blank map to fill in as we fill the states in on the promethean board. I color code each region as well. We review each region daily for a few days, then add the next region. It usually takes a month to learn them all, and then I give them the exact same map to practice with and the same map again for the test.
There are lots of online links for interactive maps and games you can use. Check out
http://www.sheppardsoftware.com/web_games.htm