A safe environment is a prerequisite for productive learning. Using a unique panel data set of survey responses from New York City middle school students, the article provides insight into the relationship between feelings of safety in the classroom and academic achievement. The survey data include the reported feelings of safety for more than 340,000 students annually from 2007 to 2010 in more than 700 middle schools. Findings show a consistent negative relationship between feeling unsafe in the classroom and test scores. The study provides insight into the mechanisms through which feeling unsafe in the classroom relates to test scores and presents multiple robustness checks to support the central finding.