Let me share with you an interesting article from The Washington Post about the teacher of an all-black class in a high school in Alexandria, Va., who expressed his frustration at how poorly the students were performing. The class included both native-born African-Americans and kids who had emigrated from Africa. In a moment of exasperation, the teacher blurted out this question to the native-born students: "Why don't you guys study like the kids from Africa?" One of them shot back the answer. The kid replied, "It's because they have fathers who kick their butts and make them study." Another student...