Assessing students’ equality of opportunity in OECD countries. The role of national and school-level policies

This article analyses the relationship between equality of opportunity and the characteristics of the educational system, jointly considering country- and school-level policies. Because school social environment represents a fundamental channel in shaping educational opportunities, we consider all policies, recorded in PISA 2012 dataset, that affect the sorting of students to schools. We show that including sorting policies enriches the explanation of the socio-economic gradient, that is, the association between students’ performances and parental background, with respect to previous studies including only country-level features. The negative impact of early tracking on equality of opportunity is overvalued without including other sorting policies, while grouping students’ within-school by ability increases the socio-economic gradient and a greater students’ heterogeneity in the school reduces the gradient.