Excuse me?! Fostering it? What on Earth do you mean?
Christ, schools are responsible for everything it seems. The question is : what are parents doing? School do A LOT - pastoral care lessons, assemblies, community police officer teaching programmes etc. But the real problem is violence and its prevalence across society. Thus it has always been. Solve that and you solve most things.
A pupil at our school was involved in gang violence that started via a WhatsApp group. A young boy from the rival gang was killed, our pupil was so badly beaten we thought he wouldn't make it and has been in hospital over 6 months. The community response? Reciprocal violence.
I'm not sure of the answer, but funding to help parents parent well in such communities is a damn good place to start - starting at the ante-natal and pre-natal stage. By the time they reach us at age 11-12 lots of the damage is done.
I have 2 teen DS (and a pre-teen) and live in a big city. We parent responsibly - clear boundaries/ open communication/ know their friends/ movements- but many, many parents don't/ can't/ won't.