● First, they demand that schooling take the form of a graded hierarchy, which requires students to climb upward through a sequence of grade levels and graded institutions and to face an increasing risk of elimination as they approach the higher levels of the system. The result is a system shaped much like a pyramid. As students ascend through high school, college, and graduate or professional school, they move into an atmosphere that is increasingly rarefied, as the numbers of fellow students begin to fall away and the chance for gaining competitive advantage grows correspondingly stronger. And from the social mobility perspective, the chance to gain advantage is the system's most salient feature. There is convincing evidence that consumer demand for this kind of educational distinction (rather than a societal demand for human capital) has been largely responsible for driving the extraordinary upward expansion of education in the U. S. during the last 150 years.