This article describes a children's opera about bullying that was presented to five classrooms in three schools and evaluated with a pre-post design. Data were available for 104 Grade 4 and 5 students who completed a bullying prevalence survey and bullying knowledge quiz before and 6 weeks after the opera. Bullying knowledge increased significantly and there was a significant decrease in self-reported victimization. There was a significant gender by time interaction indicating that boys reported less bullying whereas girls reported more bullying over time. Findings are discussed in terms of the arts as media for bullying prevention. (Contains 1 table.)