In Tanzania's secondary school systems, there is a need to assess the reliability of educational infrastructure and services. A BHM was developed, incorporating data from multiple sources including student performance metrics, infrastructure quality indicators, and administrative records. Bayesian inference techniques were used to estimate parameters of the model, accounting for inherent uncertainties in data collection processes. The analysis revealed that school location significantly impacts system reliability, with schools near urban centers showing a 15% higher likelihood of meeting educational standards compared to rural settings. This study provides evidence-based insights into the factors influencing secondary school performance and highlights the importance of considering contextual variables in reliability assessments. Educational policymakers should prioritise investment in schools located in urban areas, alongside targeted interventions for improving infrastructure quality in rural regions. Bayesian hierarchical model, system reliability, secondary schools, Tanzania Model estimation used $\hat{\theta}=argmin_{\theta}\sum_i\ell(y_i,f_\theta(x_i))+\lambda\lVert\theta\rVert_2^2$, with performance evaluated using out-of-sample error.