In this article we share exploratory findings from a study that captures microaggressions (MAs) in vivo to shed light on how they occur in classrooms. These brief and commonplace indignities communicate derogatory slights and insults toward individuals of underrepresented status contributing to invalidating and hostile learning experiences. Our aim is to expand the ways in which we research and think about MAs in educational settings. Our data are drawn from structured observations of 60 diverse classrooms on three community college campuses. Our findings provide evidence that classroom MAs occur frequently-in nearly 30% of the observed community college classrooms. Although cultural/racial as well as gendered MAs were observed, the most frequent types of MAs were those that undermined the intelligence and competence of students. MAs were more likely to be delivered on campuses with the highest concentration of minority students and were most frequently delivered by instructors. We conclude by reflecting on the implications of these events for classroom climate and make recommendations for both future research and practice.