Gender-based violence (GBV) prevention interventions in secondary schools of Dar es Salaam, Tanzania are underpinned by protective behaviors that aim to reduce GBV incidents. The research employed a qualitative approach to collect data from interviews with school administrators and students, analysing themes related to GBV prevention strategies. Findings indicate that while most schools have implemented protective behaviour programmes, there is room for enhancing their effectiveness through more targeted interventions. The study concludes that further research into specific protective behaviors and their implementation in schools can lead to more effective GBV prevention efforts. Recommendations include developing culturally sensitive GBV education materials and training school staff on how to recognise and respond to GBV incidents effectively. Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.