Persistent racial disparities in students' disciplinary outcomes have been one of the most concerning educational policy and equity topics for decades. Despite the hypervisibility of Black students in school discipline conversations, research and practice evade a focus on anti-Black racism. In this essay, we draw from Black Critical Theory (BlackCrit) to present a theoretical framework that researchers and educational stakeholders can use to specify, study, and understand antiblackness in school discipline. We outline and discuss six interrelated theoretical constructs of the Antiblackness in School Discipline framework: (a) "Trading Away the Black," (b) "Whites as Propertied," (c) Intersecting Blackness, (d) Racial Neoliberalism, (e) "La Petite Misère," and (f) Internalized Racism. Examples of studies providing empirical support for these theoretical tenets are also discussed, and suggestions for utilizing this framework in scholarship, policy, and practice are also offered.