Obesity among urban youth in Cairo, Egypt, has become a significant public health concern. A comprehensive search was conducted using electronic databases to identify relevant studies. Studies were included if they met specific criteria related to school-based interventions, BMI changes, and physical activity levels within a defined population. The review identified several studies showing mixed results regarding BMI change indices but highlighted increased physical activity levels among participants in some intervention groups. While the effectiveness of school-based obesity prevention interventions varied, there was evidence suggesting improved physical activity levels among urban youth in Cairo. Further research is needed to establish consistent and sustained improvements in both BMI change indices and physical activity levels through targeted school-based programmes. School-Based Interventions, Obesity Prevention, Urban Youth, BMI Change Indices, Physical Activity Levels Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.