Public secondary schools in France are strongly marked by the socio-demographic and academic characteristics of their pupils, their urban environment and the courses they offer. These factors of differentiation are the basis of a classification of schools into five groups: «privileged urban», «under-privileged urban», «small», «socially mixed, under-privileged» and «socially mixed, privileged» schools. This classification also reveals divergent academic profiles. The education authorities in Lille and the French overseas départements, or even Paris and Versailles, have certain similarities whilst being very different from the others. Moreover, within the same authority, differences can exist between départements.