This study tests the impact of adding Restorative Practices within secondary schools implementing the Diplomas Now turnaround model in 8 large U.S. urban districts on: (a) the severity of disciplinary problems in these schools, (b) the probability that students would be suspended three days or more during the school year, and (c) the chronic absenteeism rate. We conducted a school-level randomized control trial in 33 schools--17 treatment and 16 control--within 12 randomization blocks. The combined intervention was implemented in the treatment schools during the 2014-2015 and 2015-2016 school years. The results from the final year on the pre-specified primary outcomes indicate that the intervention significantly reduced the severity of discipline problems in treatment schools (ES = -0.13) and the probability that students would be suspended 3 or more days (OR = 0.66); reductions in chronic absenteeism were only marginally significant.