Best all-inclusive Social Studies curriculum: Heritage Studies by BJU Press. This curriculum includes Geography, Economics, Government, American History, World History, and Culture, so you don't have to worry about finding a separate curriculum for each. Available for grades 1-12.
Best states & capitals games online:
- SheppardSoftware.com - a range of difficulty levels and different styles of games. The most challenging states/capitals games here challenges you to choose the correct capital for a given state from the entire list of 50 displayed capitals - surprisingly very difficult. There are also many more geography-related games and resources on this website.
- YourChildLearns.com - this states/capitals game gives you a capital which you must drag onto the correct unlabeled state - very challenging. This website also has many other geography puzzles and games, which can be found here.
- KidsGeo.com - this is a nice multiple choice option which shows you a given state, and asks you to choose the correct capital from 4 options. Again, many more geography games and resources are on this website, and worth looking at.