The endorsement of anti-corruption norms is a normative assumption in legal systems with freedom of information acts, where citizens are expected to act as monitors of the public service. Tolerance of corruption counteracts this assumption. We studied tolerance of corruption among 8th graders from Latin-American samples of the International Civic and Citizenship Study 2009. We proposed a model where associations between students’ socioeconomic status (SES) and tolerance of corruption are explained by civic knowledge, authoritarianism and open classroom discussion. This model accounted for 36–43% of the variance within schools, and 87–96% of the variance between schools, across six countries. The socioeconomic gap in tolerance of corruption was mainly present between schools. In addition, students with higher civic knowledge were less tolerant of corruption, partially explained by authoritarianism, while open classroom discussion also had indirect associations with tolerance of corruption.