I find it disgusting and utterly ridiculous that we have to have this conversation and feel it is a sad commentary on the current state of affairs in the U.S. But to answer your question on how to stop school violence, I'd say we need more resource officers, more and better control over access to school grounds, metal detectors and on-site mental health counselor(s). I completely disagee with arming teachers as I feel that more guns is not the solution. However, if that were to pass, and teachers could choose to conceal carry, then I would require each to undergo annual weapon training, register with their school and local authorities so that there is a comprehensive list of who has been approved to have a weapon on school property, an annual mental evaluation and liability insurance.