How could I have forgotten -- there's a scene in DON'T TRUST THE MAFIA that is perhaps the ultimate Italian crime kid kill:
If I remember correctly (I'm too tired to dig out the movie and check my memory), a whole class of panicky schoolchildren are fleeing after hearing some gunshots in one scene, and one of the crooks is right around the corner. As the kids round the bend, the criminal machineguns the whole lot of them. Brutal stuff.