This article demonstrates how using feedback mechanisms or "loops" as heuristic devices can help ethnographers explain the interior logic, robustness and contradictions within complex educational assemblages. After reviewing the use of feedback mechanisms in the natural and social sciences, particularly practice theory, the article presents two feedback loops drawn from the first author's four-year ethnographic study of class culture and neoliberal schooling in suburban Ohio, USA. The first identifies "hypercredentialing" as the key process underlying the production of the performative worth of achievement-oriented students; the second identifies "reflexive awareness" as a key process underlying the insufficient performativity of under- and lower-achieving students. The article uncovers hidden dynamics regarding neoliberal governmentality and performativity within a particular educational context and, more broadly, shows how using feedback mechanisms enables ethnographers to make cultural processes, as well as their interpretations of them, more transparent.