Geography/social studies teachers, I found a tool you might be able to use with your students.  Sporcle’s games include several geography games (the US and its capitols, the six inhabited continents) that will challenge your students to learn more about their world.  As a bonus, when your students become curious about these countries, they can click on the most missed links on each game, which will not only list the states or countries in order that most people get them correct, but also have Wikipedia links to articles about that place.  As students learn their geography, the challenge will be to improve their speed.  A caveat: the games are hosted on a “sporting oracle” site that could potentially be used for betting purposes.  Another warning: the games are really addictive.