Since the late 1990s, increased public and academic attention has been focused on topics related to bullying and peer aggression in schools, yet these behaviors have proven difficult for schools to address. Using data from an ethnographic study of two rural elementary schools in the Midwestern United States, I make both methodological and theoretical contributions to the literature on this topic. Methodologically, I show that examining 'minor' aggressive behaviors in schools reveals the way that more serious issues are also normalized. Theoretically, I show that students and adults actively construct shared understandings in these schools regarding the normalization of aggression, increasing the frequency of these behaviors, limiting the ability of adults to effectively deal with them, and contributing to the stigmatization of students who do not accept them. These findings add to our understandings of bullying and aggression in schools and the relationship between school cultures and peer cultures.