Zambia has high rates of violence against children and low rates of secondary school completion, especially among girls. In 2023, the Keeping Girls in School (KGS) program under the Girls’ Education and Women’s Empowerment and Livelihoods (GEWEL) project, launched the Empowerment Pilot (EP), an ambitious intervention to reduce school-related gender-based violence (SRGBV). KGS embedded mixed-methods impact evaluation into the pilot to produce rigorous evidence on its effectiveness. The study showed that more than half of secondary school students in the three pilot districts experience violence at school. The EP did not reduce overall levels of violence in intervention schools. Discussion of violence and bystander reporting increased as a result of the EP, but overall levels of reporting remain low. There was a slight improvement in boys’ attitudes towards gender roles, but not girls’ and the intervention had no impact on attitudes and norms related to SRGBV. The EP was ineffective at reducing school violence due to design and implementation gaps. Though intended as a multi-component intervention, it operated mainly as a club-based model with limited school-wide reach. Key elements, such as teacher engagement and parent involvement were inconsistently delivered, while social norms continued to stigmatize victims and excuse perpetrators. Scalable solutions require consistent implementation, broader participation, and strong accountability.