Disciplinary systems are designed to control. At School James, an inner-city elementary school in the Midwestern United States, a highly detailed system of rules and punishments is supposed to control students. Various rules minutely regulate almost every conceivable aspect of students’ appearance, conduct, interactions, and movement. Drawing on my fieldwork at School James, and Michel Foucault’s theory of discipline, this article argues that the meticulous attention to detail that is designed to ensure the effectiveness of rules and punishments creates various inconsistencies that undermine the disciplinary system in practice. These inconsistencies arise out of the structure of the disciplinary system itself, and the interplay of teachers’ and students’ agency in handling rules and punishments. As a result, the disciplinary system not only falls short of achieving the desired levels of control, it also creates tensions between students and teachers who are subjected to its constraints in their daily interactions.