For most of us, "geography" conjures memories of classroom tedium and efforts to memorize the names of the United States in alphabetical order. But geography - from the Greek geographia, "to write about the earth" - is actually an enduringly fascinating subject. And there's no more agreeable way of learning about the planet than enjoying these 48 Knowledge Cards. Imparting their information in question-and-answer and match-up formats, they illuminate such interestingly murky geographical corners as: How heavy is Earth?, Where is the world's tallest waterfall?, What are the Seven Summits?

The questions and answers in this deck were compiled by the staff of Scientific American, so you know they're accurate. They'll bring you up to speed on a subject that will stir your curiosity and invigorate your mind.