Teachers play an important role in promoting a positive school climate, which in turns supports academic achievement and positive mental health among students. This study evaluated the impact of a pre-service teacher education course addressing a range of contributors to school climate. Participants included a cohort of 212 pre-service teachers (75.2% female) who were surveyed during the first week of their teacher preparation program. A second cohort of pre-service students (n = 199, 60.8% female) was used as a comparison group. Pre- and post-tests demonstrated positive gains in the knowledge about bullying and self-efficacy in responding and reporting to incidents of students' exposure to violence. Changes in moral disengagement were associated with improvements in knowledge, whereas personal experience with violence predicted changes in self-efficacy. Findings underscore the need for specific instruction in the area of promoting school climate.