It is probably an extreme example, but there is always "The Street Stops Here", a docu. about Bob Hurley, who is simply obsessed with keeping kids raised in dire poverty out of prison through the education system.
Of course he coaches basketball but that's almost peripheral (although he also loves winning ). His program is tightly integrated with the rest of a Catholic school. These kids live in a state of despair. He will fight this until his last breath. And he does not fight fair. Bob is a retired parole officer.
If anything, the film leaves me with the unsettling feeling that this is a very hard problem. It'd take decades of failure as a parole officer to make one Bob Hurley, and there seems to be only the one.