In advanced economies, schooling is a near-universal and highly structured institution. During the most impressionable times in their lives, children and adolescents go nearly every day to sit in the same pattern of classes with the same peers. In theory, students both within and across schools are supposed to learn the same things, at approximately the same time, and engage in similar rituals. And yet, this level of standardization often leads to substantively different outcomes across groups. This course investigates the structure of schools and the achievement hierarchies within and across them.