School districts historically approached conflict-resolution from the perspective that suspending disruptive students was necessary to protect their classmates, even if this caused harm to perceived offenders. Restorative practices (RP) – focused on reparation, accountability, and shared ownership of disciplinary justice – are designed to address undesirable behavior without harming students. We study Chicago Public Schools' adoption of RP and find that suspensions and arrests decreased, driven by effects for Black students. We find null effects on test-score value added, ruling out meaningful average declines. We estimate a 15% decrease in out-of-school arrests, consistent with RP substantively changing student behavior.