This paper studies the impact of compulsory schooling on violent behaviour and victimization in school using individual-level administrative data matching education and criminal records from Queensland (Australia). Exploiting a legislative increase in the minimum dropout age in 2006, this study defines a series of regression-discontinuity specifications to show that compulsory schooling reduces crime but increases violent behaviour in school. While police records show that property and drugs offences decrease, education records indicate that violence and victimization in school increase. Thus, prior studies that fail to consider in-school behaviour may over-estimate the short-run crime-reducing impact of compulsory education.