The present study aims to understand the implementation of a flow correction policy in a municipal school in Rio de Janeiro. To do so, we investigated teachers, principals and students perceptions on the project, analyzing how they influence their discretion. Among the theoretical references are the contributions of Sociology of Education, especially Bourdieu s ones concerning school failure and school agents judgements, and the studies on street-level bureaucracy inaugurated by Lipsky. Regarding the methodology, we first analyzed the official documents related to the flow correction policy implemented in Rio de Janeiro, based on Lima s (2016) review on the subject. Secondly, we proceeded to an exploratory research into School Census data related to the selected school. The empirical material was generated through semi-structured interviews with 32 subjects, including teachers, principals, assistants and students from regular and accelerated learning classes. The study concludes that there is considerable resistance to the flow correction policy, especially due to the concentration of those students identified as problematic in the same classes. There is a prevailing perception of overage students as undisciplined, uninterested, or even as cognitively impaired, holding such students accountable for their own failure. The implementing agents seem to guide their discretionary actions based on a practical-moral judgement that differs worthy students from unworthy ones, responding to their perceived needs differently. By way of conclusion, we discuss to what extent the understanding of school education as a public right can be resignified as a private reward in a context of work overload and scant resources.