Scholars find that social dynamics in online environments help explain variation in cyberbullying victimization. The current study examines how students' in-person activities at school shape the odds of cyberbullying victimization. This focus is motivated by opportunity theory, which emphasizes that victimization can be shaped by involvement in dangerous activities, exposure to potential aggressors, and the suitability of targets in the eyes of potential aggressors. Key aspects of the students' in-school activities include involvement in fighting and participation in various extracurricular activities. These elements are analyzed using data from the 2013 School Crime Supplement to the National Crime Victimization Survey based in the United States. Findings indicate opportunity theory is applicable to explaining cyberbullying victimization regarding exposure to aggressors via extracurricular activity participation at school.