This paper reports the results of a study aimed at understanding the processes governing the construction of educational inequalities in French classrooms, the French school system being particularly unequal. Traditional explanations have focused on the factors governing the production of inequalities but have not always shown how these factors translate into learning inequalities in class. Consistent with relational approaches, the study draws on ethnographic research conducted over an 18-month period in 6 socially contrasting Parisian schools. Both students from wealthy families considered to be 'high-achieving' and students from poor families viewed as being 'low-achieving' were observed over the course of full school days to understand the factors that lead them to develop different activities. The evidence suggests that children interpret teacher expectations very differently, although the same expectations were observed in all the classes observed during the study. These expectations point to an invisible curriculum operating alongside the formal curriculum and generally perceived only by high-achieving students, who are able to grasp and understand it through their prior socialization. A further characteristic of the invisible curriculum is that it is rarely made explicit by teachers. This finding highlights the need to further examine explicitation strategies in schools.