Despite intense public interest in keeping guns out of schools, next to nothing is known about the effects of gun control policies on youth gun carrying or school violence. Using data from the Youth Risk Behavior Surveys (YRBS) for the period 1993-2013, this study is the first to examine the relationship between child access prevention (CAP) gun controls laws and gun carrying among high school students. Our results suggest that CAP laws are associated with a 13 percent decrease in the rate of past month gun carrying and an 18 percent decrease in the rate at which students reported being threatened or injured with a weapon on school property. In addition, we find that CAP laws are associated with a lagged decline in the probability that students miss school due to feeling unsafe. These results are concentrated among minors, for whom CAP laws are most likely to bind. To supplement our YRBS analysis, we collect a novel dataset on school shooting deaths for the period 1991-2013. We find that while CAP laws promote a safer school environment, they have no observable impact on school-associated shooting deaths.