There are few avenues of life in which violence is sanctioned; fewer still in which it is productive and necessary. Working demolition (“demo,” to its initiates) on houses is one of them. This was what I did this summer. Not with plastics explosives or wrecking balls: with screwguns and sledgehammers and crowbars. And after 10 long months of shepherding 11 and 12-year-olds through preadolescent turmoil--through that brief intersection of childhood enthusiasm and pubescent confusion--it felt pretty damn good. Like…