Youth mental health issues are increasingly prevalent in urban schools across Ghana, necessitating effective interventions. An action research approach was employed to develop, implement, and assess a tailored peer support programme in two urban schools. Data collection included surveys, interviews, and observations. Findings suggest that the peer support programmes significantly reduced stigma around mental health issues (75% reduction) and improved students' self-esteem by fostering positive social interactions among peers. Peer support programmes were effective in creating a more inclusive school environment where students felt supported, leading to better mental health outcomes. Future research should explore scalability of these findings. School administrators should integrate peer support programmes into their mental health strategies and provide ongoing training for facilitators to sustain the positive impacts observed.