The scene at Detroit's sprawling, gritty Redford High School seemed like a % real-life replay of Blackboard Jungle. Throngs of students, some armed with knives, roamed the graffiti-covered halls, smoking marijuana, playing touch football and frequently fighting. Only about half the mostly black student body of 2,800 showed up for classes on any given day. The school's administrators had lost control. No wonder a monitoring commission set up by a federal court described Redford as the worst high school in Detroit.
That was before Joe Greene arrived three years ago to take over as principal. Greene, a soft-spoken Mississippian with 18...