States and districts are revising discipline policies to reduce out-of-school suspensions (OSSs), but the consequences of these reforms are largely unknown. We examine a reform in Philadelphia that prohibited OSS for classroom disorder infractions. Employing a difference-in-differences approach, we examine the relationship between the reform and student suspensions, achievement, and attendance. For students suspended before the reform, classroom disorder OSS decreased and attendance (but not academic achievement) improved following the reform. Postreform changes in peer outcomes varied with school-level implementation: in schools that eliminated classroom disorder OSS, peer math achievement and attendance were unaffected, whereas peer math achievement declined and attendance decreased in schools that did not fully implement the district-level reform.

中文翻译：

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校纪改革：校级政策执行及停学学生及其同龄人的后果

各州和地区正在修订纪律政策以减少校外停学 (OSS)，但这些改革的后果在很大程度上是未知的。我们研究了费城的一项改革，该改革禁止 OSS 用于课堂混乱违规行为。我们采用差异中的差异方法，研究了改革与学生停学、成绩和出勤之间的关系。对于改革前停学的学生，改革后课堂混乱 OSS 减少，出勤率（但不是学业成绩）提高。同龄人成果的改革后变化因学校层面的实施而异：在消除课堂障碍 OSS 的学校中，同龄人数学成绩和出勤率不受影响，