Coach needs to teach ex-assistants a lesson.

Give Coach--oops, Professor--Mike Krzyzewski credit. He has what is arguably the best resume of any active coach in college basketball, going 27 years, three national championships and more than 600 wins without a whiff of scandal.

No wonder Duke's Fuqua School of Business recruited him to lead a new think tank. In October, Duke President Nan Keohane announced the creation of the Fuqua/Coach K Center of Leadership and Ethics. Krzyzewski will teach there during the off-season. His official title will be "executive-in-residence."

But teachers of ethics are also measured by the probity of their pupils. Socrates owed his fame partly to training Plato, and Plato, in turn, for tutoring Aristotle. Beside their examples, Professor K doesn't quite look like a philosopher king.

The basketball programs of two of his pupils--Quin Snyder, a former player and assistant coach and a Fuqua MBA, and Tim O'Toole, a former assistant coach--face allegations of wrongdoing. Snyder's University of Missouri program is being investigated by the National Collegiate Athletic Association. An internal committee at O'Toole's employer, Fairfield University in Fairfield, Conn., is probing possible misdeeds.

Missouri's troubles stem from the bad behavior of former player Ricky Clemons. He was dismissed after violating his work-release sentence for choking his ex-girlfriend and preventing her from leaving his apartment. She claims that Clemons got help cheating in class from coaches and was paid. At Fairfield, former players told the Connecticut Post that coaches gave cash to players and did their schoolwork. The school's president has hired a law firm to help with the investigation.

Jim Gray, associate dean for marketing and communications at Fuqua, points out that none of this impugns Krzyzewski's integrity. "There's never been any hint of anything unethical about the Duke basketball program," he says.

Gray's right, of course. But Professor K may want to reserve a few slots in his Fuqua classes for his coaching alums.