This paper examines the short-term effect of school on juvenile crime. To do so, we bring together daily measures of criminal activity and detailed school calendar information from 29 jurisdictions across the country, and utilize the plausibly exogenous variation generated by teacher in-service days. We find that the level of property crime committed by juveniles decreases by 14 percent on days when school is in session, but the level of violent crime increases by 28 percent on such days. Our findings suggest that both incapacitation and concentration influence juvenile crime.