Medium of instruction policies and efficacy of educational systems in Sub-Saharan Africa

The paper explores the role of language use in education policies in mediating learning outcomes and skill formation in Sub-Saharan Africa. The analysis shows that countries that employ indigenous languages in primary schooling are the most efficient in imparting human capital. The students instructed using local languages are 33 to 46 percentage points more likely to be able to read after five years of schooling, compared to students instructed using the colonial language. I discuss the complementarity between language and other educational inputs to shed light on why most educational interventions seem to have limited effects in Sub-Saharan Africa. Finally, I show reporting effect sizes using standardized tests scores provide little guidance in interpreting the importance of the magnitude of the treatment effect and might lead to erroneous conclusions regarding the effectiveness of interventions.