Class size is one of the predominant topics in educational policy debate, as its impact on academic performance has not always yielded consistent findings. Nevertheless, less emphasis was paid to noncognitive outcomes such as well-being and behavioral issues. This study employs rich administrative and survey data to investigate the effects of class size on students’ bullying and violent behavior as well as cognitive abilities tests. The study uses the maximum class size rule to create a regression discontinuity (RD) relation between cohort enrollment size and class size in the public and the United Nations Relief and Works Agency school system in the West Bank. Further, this study provides evidence that there is no violation of the RD assumptions resulting from discontinuities in the relationship between enrollment and students’ household background at cutoff points induced by a maximum class size rule. The findings suggest that class size reduction improves the quality of life for children by mitigating bullying and violent behavior among pupils, which might have long-term adverse effects on academic attainment. Finally, peer relationships and mental health problems are identified as potential mechanisms through which class size influences self-reported levels of bullying and violent behavior among students.

中文翻译：

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班级人数减少、欺凌和暴力行为：来自约旦河西岸学校的证据

班级规模是教育政策辩论中的主要话题之一，因为其对学业成绩的影响并不总是能得出一致的结论。然而，人们不太重视非认知结果，例如幸福感和行为问题。本研究利用丰富的管理和调查数据来调查班级规模对学生欺凌和暴力行为以及认知能力测试的影响。该研究使用最大班级人数规则在西岸公立学校系统和联合国救济和工程处学校系统的队列入学人数和班级人数之间建立回归不连续性（RD）关系。此外，本研究提供的证据表明，在最大班级人数规则引起的截止点处，入学率和学生家庭背景之间的关系不连续，因此不违反 RD 假设。研究结果表明，减少班级规模可以减少学生中的欺凌和暴力行为，从而改善儿童的生活质量，而这些行为可能会对学业成绩产生长期的不利影响。最后，同伴关系和心理健康问题被认为是班级规模影响学生自我报告的欺凌和暴力行为水平的潜在机制。