Survey among students of 15 years old about how they perceive themselves in general, and their academic, social and civic competence in particular. Self perception of academic competence / self-perception of social competence / general self-concept like feelings of being satisfied with oneself and experiencing feelings of well-being, dissatisfaction with the self / civic competence: knowledge about society, democratic attitudes, political engagement, participation in political discussions, following news / gender / ethnicity / educational level of parents / time spending / parenting style of students' parents / type of secondary school / denomination of school / CITO score