This dissertation aims to understand the contribution of schools to reducing bullying behaviors and, in turn, to examine the benefits for students of attending a school that effectively reduces bullying. In doing so, this dissertation contributes to the literature on bullying by (a) locating the school as a key environment in social-ecology of bullying, which is central to prevention efforts; (b) showing empirically that schools have an effect on students' bullying behaviors; (c) offering a better understanding of the cost of bullying; and (d) examining the dimensions of schools -- with a special focus on relational measures -- that predict reductions in bullying. In study 1, I aim to identify the effect of schools on bullying and, in turn, the effect a reduction in bullying on students' educational outcomes. Further, I show that these effects differ by gender and the gender composition of a school. I leverage detailed longitudinal data on the entire population of 9th graders in Chile to document these effects. Using a value-added approach, I show there is variation in whether schools increase bullying relative to other schools. This suggests that schools affect students' bullying experiences. Second, I show that attending a school that reduces bullying benefits students' victimization experiences, test scores, attendance, and dropout rates. While victimization is more prevalent among boys, I find that the effects on attendance and dropouts are larger for girls. Finally, I examine the relationship between school gender composition and bullying value-added. I find that the share of boys in a classroom predicts an increase in bullying in secondary schools, driven in part by single-sex schools. I thus provide evidence that schools contribute to bullying behaviors and that bullying takes a toll on students' educational outcomes. In study 2, I attempt to better understand what school organization measures predict reductions in the fear of bullying. Previous work has focused mostly on individual-level factors that contribute to bullying. In contrast, this paper uses an ecological framework and instead centers the role of schools, as institutions, in reducing the fear of bullying. First, I develop a measure of value-added to isolate the contribution of schools to reducing the fear of bullying. I leverage uniquely detailed survey data from Chicago Public Schools, which includes questions on the fear of bullying and socioemotional development, as well as educational outcomes. I validate this measure by showing that attending a school that reduces the fear of bullying has positive effects on students' fear of victimization, socioemotional development, and long-term educational outcomes. Second, I examine dimensions of school organization that predict reductions in the fear of bullying. To do this, I use measures of the 5 Essentials framework developed by the Chicago Consortium for School Research. I find that having a supportive environment, as perceived by students and teachers in the school, is the strongest predictor of school reductions in the fear of bullying. In study 3, I perform a secondary analysis of a randomized controlled trial that tested the KiVa Anti-Bullying program in 39 schools in Chile. The KiVa Antibullying Program is a school-based intervention that has gained widespread recognition for its effectiveness in reducing bullying behavior. The program is informed by recent research that stresses the social role of bullying, by which bullies harass lower-status peers to achieve or maintain social status. While prior evaluations of the program found KiVa reduced bullying, they did not examine its effect on other outcomes. This study is the first large-scale experiment of an anti-bullying program to examine longer-term educational outcomes and school climate. It finds that the KiVa program significantly improves students' educational attainment by reducing dropouts and improves the quality of the schooling experience by reducing bullying and improving relationships within schools. Students in the treated schools reported less bullying, had lower dropout rates, and reported better relationships with the school community. Together, these three studies provide evidence that schools affect bullying behaviors, and that attending a school that reduces bullying has significant, positive impacts on students' development and educational outcomes. Further, it provides suggestive evidence that investing in building a more supportive environment that centers improving student-peer and student-teacher relations is a promising strategy for reducing bullying. I conclude by discussing lessons for researchers and policy-makers. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]