This paper provides empirical evidence on how aspirations are formed and affect individual behavior, decisions, and paths in the context of education. Using unique data on aspirations, academic performance and actual track assignment to high school of French ninth graders, we show that low-SES students have lower aspirations than their equally-achieving high-SES classmates, and that track assignments to high school the next year are even more unequal due to dysfunctional dynamics: first, both low aspirations and low SES are associated with slower academic progress over the year. Second, aspirations and parental SES play a role in track assignment independent of one’s academic performance. Our results suggest that, in France, an aspirational trap at school contributes to the poverty trap, leading to the perpetuation of social inequalities.