Student performance following the conversion of single-sex schools to co-education: evidence from Colombia

Whether to convert existing single-sex schools into co-educational ones remains an open policy question in many countries, yet causal evidence on how such conversions affect academic performance is limited, particularly in developing country settings. This study uses quasi-experimental evidence from Colombia to examine changes in students´ academic performance following the transition from single-sex to co-educational schools. Analysing the conversion of single-sex schools over 20 years with a staggered difference-in-differences approach, we find that academic performance in mathematics declines for males in former male-only schools, while estimates for girls in former female-only schools remain statistically inconclusive.