What has happened to increase the consequences of social background on academic performance?

The considerable level of social inequality in educational performance is a major factor in educational equity. In this work, we try to highlight the factors behind the recent increase in these inequalities by means of indicators available in the PISA survey data (2003 and 2012). First, we examine the evolution of the different components of the multicriteria indicator by which the OECD most often measures social environment. Then, we model, through a path analysis, the breakdown of the effect of parents' occupational status on performance in order to grasp how this operates. Both external and internal factors to the school are used. Our analysis emphasizes the responsibility of the school in the increasing of educational inequalities in the sense that the school converts social inequalities, which have changed little, into learning inequalities more now than in the past. This is evidenced, inter alia, by the role of segregation between institutions and also cultural factors, in particular the importance of having books in the family home.