At first, your students don’t know anything because you teach poorly, and you know this. Then, you become happily aware that some students are learning. You know that other students still aren’t, but you are pedagogically nearsighted and can make only blurry distinctions between the two camps. Your teaching improves and the ranks of the Is Learning camp swells and you know the members of the Isn’t Learning camp by name. You develop better methods of tracking achievement and you know exactly what the students who aren’t learning haven’t learned. Moreover, as you teach, you begin to anticipate the material that will confuse these students. You realize that your intervention can effectively transfer a student from one camp to the other. At a certain point, the technical challenges to increasing student achievement disappear, but the moral challenge remains. Will you do it? Every day, every hour, every student for 180 days, will you do it?