Secondary school systems in Tanzania face challenges related to resource allocation, infrastructure development, and educational outcomes. A randomized field trial was conducted among secondary schools across Tanzania. Schools were randomly assigned to either an intervention group or a control group, with pre- and post-intervention assessments used to measure yield improvement. Results indicate that the intervention led to a statistically significant $Y = 0.8X + 15$% increase in student academic performance (95% CI: [6%, 10%]), where Y represents the percentage of students achieving higher scores and X is the proportion of schools implementing the intervention. The randomized field trial demonstrated that targeted interventions can effectively improve educational outcomes, providing evidence for policy makers to enhance secondary school systems in Tanzania. Policy makers should prioritise scaling up successful interventions based on this study's findings to achieve broader improvements in education quality and equity.