This dissertation is comprised of three manuscripts demonstrating that greater prevalence of teasing and bullying (PTB) in a school is consistently related to lower school passing rates on the Virginia's mandatory achievement tests, the Standards of Learning (SOL) exams.The first manuscript investigated the relations between PTB, as reported by students and teachers, and the percentage of students who passed SOL exams. Measures of PTB were obtained from a statewide survey of 7,304 ninth grade students and 2,918 teachers aggregated into school level scores for 284 Virginia high schools. Hierarchical regression analyses conducted at the school level found that PTB scores predicted schoolwide achievement on the SOL exams. These findings could not be attributed to the proportion of minority students in the school, student poverty, school size, or personal victimization, which were statistically controlled.The second manuscript examined the relations between PTB as reported by high school administrators and school performance on SOL exams. In addition, this study aimed to show that the use of evidence-based bullying prevention efforts is positively associated with test performance. School administrators from 301 high schools in Virginia were surveyed on PTB as well as the types of bullying prevention efforts currently used in their schools. School administrator assessments of PTB were negatively associated with schoolwide achievement and evidence-based efforts to prevent bullying were positively associated with schoolwide achievement.The third manuscript examined the relations between PTB and schoolwide achievement on SOL exams as well. However, this research adds to the literature by BULLYING AND ACHIEVEMENT extending the findings to middle schools and by investigating the mechanism behind this relation. Specifically, this research examined how student engagement in school mediates the relations between PTB and academic achievement. Measures of PTB and student engagement were obtained from a statewide survey of 29,203 seventh and eighth grade students and 6,298 teachers from 271 Virginia middle schools. Hierarchical regression analyses conducted at the school level found that the PTB as perceived by students as well as teachers was predictive of schoolwide achievement on the SOL exams.Engagement was found to be a partial mediator in the association between PTB and test passing rates. These findings were not accounted for by the proportion of minority students in the school, student poverty, school size, or personal victimization, which were statistically controlled. These results support notion that PTB is related to student performance, in part, because PTB decreases student engagement in the academic process which, in turn, decreases student achievement on high stakes testing.In total, these three studies have demonstrated the association between PTB and academic achievement in both middle and high schools. Further, this relation has been shown using student, staff, and administrator reports of PTB. Althou...