Bullying is a common form of aggression experienced by school-aged children. Because bullying often happens in the classroom, teachers are integral to bullying detection and prevention. This article details how National Institute of Justice-supported researchers developed and tested an integrated coaching and mixed-reality simulation strategy for teachers called the Bullying Classroom Check-Up. The strategy is an uncommon anti-bullying strategy in that it focuses on developing skills in teachers, not students. Data from the school year during program implementation showed that teachers who used the strategy were better at detecting and responding to bullying, but were not better at preventing bullying behavior. Program impact results were not sustained in the year following implementation.