"Existing studies on single-sex schooling suffer from biases due to student selection to schools and single-sex schools being better in unmeasured ways. In Trinidad and Tobago students are assigned to secondary schools based on an algorithm allowing one to address self-selection bias and cleanly...

"Using exogenous secondary school assignments to remove self-selection bias to schools and peers, I obtain credible estimates of (1) the effect of attending schools with higher-achieving peers, and (2) the direct effect of peer quality improvements within schools, on the same population. While...

To explore whether schools' causal impacts on test-scores measure their overall impact on students, we exploit quasi-random school assignments and data from Trinidad and Tobago to estimate the causal impacts of individual schools on several outcomes. Schools' impacts on high-stakes tests are...