Seven schools in an economically challenged area of an urban school district in central California implemented mentored peer mediation programs under the guidance of a university-K-12 partnership project, Mediator Mentors. Individual student outcomes for social-cognitive dispositions, perceptions of school climate, conflict strategy choices, and standardized testing results in language arts were analyzed on the basis of assessments administered after one year of program implementation and compared to pretest values generated by student mediators and non-mediators. Attendance and student perceptions of school safety were also examined after a year of peer mediation at the schools. Overall school climate was analyzed with respect to bullying incidence and suspension and expulsion rates before and after one year of program implementation.