School climate is an important potential mechanism by which school-based prevention and intervention efforts exert their effects, although this is rarely examined in the context of child abuse prevention programs. The current study evaluated the effectiveness of a school-based child abuse prevention curriculum; the "Second Step Child Protection Unit" (CPU), on improving teachers' knowledge and attitudes toward reporting suspected child abuse and the potential role school climate has on teachers' reporting behaviors. The sample included 162 school teachers participating in a randomized controlled trial who completed assessment measures at three time-points (pretest, posttest, and 6-month follow-up). Results from the current study revealed that the "Second Step CPU" significantly improved teachers' knowledge and attitudes toward reporting suspected child abuse and there was a partial mediation effect of school climate on teacher outcomes at 6-month follow-up. These findings add to the literature on child abuse prevention by indicating that a comprehensive child safety intervention is not only effective for improving targeted outcomes, but also for improving the overall school climate. Therefore, understanding school climate as a mechanism of change may promote the successful implementation of school-based child abuse prevention programs.