This study examines the effects of microaggressions on the performance and the perceptions of students in team based learning groups (TBL). Microaggressions, which are widely studied in psychology, communicate negative messages to members of marginalized groups. The majority of research on microaggressions focuses solely on assessing respondent’s reactions after the fact using interview or survey data. My study is different because I record microaggressions as they are happening in the TBL setting. I interview participants from the TBL classes to understand their perceived microaggressions. I employ a grounded theory approach to explore the effects that experiencing microaggressions have on students in team-based learning settings. My results show that idiocultures created in these groups mediate relationships between the microaggression and the recipient’s response to the microaggression. I find that the majority of microaggressions experienced in the classroom are microinsults. In the groups, observed microaggressions are often jokes about the content or a current event. I find that the common response to a microinsult is no response at all.