It's like a dream come true for educators: free resources available wherever a web browser can operate and with nary an iota of advertising. What's not to like? What is it about this organization, whose mission is "to provide a free, world-class education for anyone anywhere," that has provoked such vitriol? Part of it is that when its videos have been watched some 217 million times. The Khan Academy videos made a stir when they arrived on the educational stage. But are they a paradigm shift or an old model in new clothes? Khan Academy has inspired both unconditional love and virulent criticism. But the controversy around the videos has sparked something truly valuable: a national conversation about math instruction and the role of technology, data, and teachers in helping students learn.