If the ridiculous 3 1/2-month tenure of New York City schools Chancellor Cathleen Black shows anything, it is that mayoral control of public schools and non-traditional school leaders are hardly the answer to the ills of urban education as modern reformers have portrayed them.

Black resigned on Thursday after she was tapped last December by her friend New York City Mayor Michael Bloomberg to succeed the departing Joel Klein even though she had no professional experience in education, and had not attended public schools.

Her approval rating was at 17 percent, according to a Marist College/NY1 released this week. Two percent of surveyed adults said she was doing an excellent job. Though public opinion polls are not a great way to choose and retain leaders, in this case, the poll reflected how Black had become a problem for the system and Bloomberg.

The mayor pushed to appoint Black, a former USA Today publisher and head of Hearst Magazines, against the recommendation of an expert panel he convened to advise him. He also needed to get a waiver for Black from state Education Commissioner David Steiner because she had none of the credentials for the job as required by state law. Steiner granted the waiver with the proviso that Black’s No. 2 would be an educator.

Now Bloomberg has picked another chancellor without public input, Deputy Dennis M. Walcott, who has advised Bloomberg on education issues for a long time, the New York Times reported.

Klein, a lawyer, of course, had had no education experience, either (and had to get a waiver from the state) when Bloomberg appointed him in 2002 to run the schools. Bloomberg picked him, and then Black, under the delusion that business management success is transferable to public education.

Bloomberg and Klein spent years hailing a rise in standardized test scores as proof of the success of their business- and test-driven school reforms -- which included attacking teachers unions and pushing for the expansion of charter schools. But last year state officials disclosed that the test scores were inflated because the tests themselves had become easier. Another problem for the Bloomberg/Klein legacy: The achievement gap didn’t improve under Klein’s long tenure.

As for Black, her very brief tenure was marked by a series of gaffes. When a parent asked her about crowding at schools, she responded with this joke: “Could we just have some birth control for a while? It would really help us” — for which she later apologized. She also used the phrase “many Sophie’s Choice” to explain the difficulty she faced in dealing with crowding, a reference to the William Styron novel about a Polish mother in the World War II Auschwitz concentration camp who had to choose which of her two children would die.

As if that weren’t enough, Black was booed at a public meeting by parents, and she booed back.

There is a reason that district leaders should come from the ranks of educators.

There is no guarantee, of course, that such experience guarantees a great leader, any more than a degree in medicine guarantees someone will be a great doctor. But it’s a good bet that education and experience make someone more likely to be successful than someone who walks into a job without them. That’s why doctors run hospitals and U.S. presidents pick surgeon generals from the medical field. They invariably don’t pick professional educators to be education secretaries, a reflection of how the teaching profession has long been viewed in this country.

It is therefore not particularly surprising that public school teachers find themselves under assault from legislators who are intent on telling teachers what and how to teach, and then linking their evaluations and pay to standardized test scores. This is called “school reform” today when it is actually nothing more than a fight over labor law.

The hiring of non-traditional school system chiefs has been popular in the past 15 years, during which we’ve seen retired Army generals, businessmen, lawyers and others tapped to run school districts because, supposedly, they have leadership ability. And mayoral control of public schools was hailed as the answer to ineffective and sometimes incompetent local school boards who engaged in petty fights, selected lousy district leaders and otherwise let the systems they were charged with watching go to hell.

But, mayoral control has proved to be hardly a panacea, not in New York York, nor in Cleveland, nor Chicago, to name a few places. Nor has the non-traditional superintendent been particularly successful. Because one former general made a good superintendent -- John Stanford in Seattle -- other districts foolishly got the idea that they could replicate his success by picking a military man. That’s how Washington got Gen. Julius Becton back in the 1990s. That didn’t go so well.

Washington former mayor Adrian Fenty won control of the school system in April 2007, and he appointed Michelle Rhee (with the support of Klein) to the top schools job. She then instituted controversial reforms that led to Fenty’s ouster as mayor last year. She reported to Fenty, who let her do whatever she wanted.

Rhee had been a teacher for about three years and then founded the New Teacher Project, which recruited teachers into the profession. During her years of teaching in Baltimore, she told an audience, she taped her students’ mouths shut because she didn’t know how else to get them to stop talking. Recently her claims of huge test score gains among her students was challenged. Though her successor has ordered an investigation, following a USA Today report, into possible cheating on standardized tests. The newspaper probe focused on one elementary school but said there were issues detected at scores of schools. Rhee has said she does not believe there was widespread cheating (after first denouncing the paper for investigating), though, as my colleague Bill Turque reported here, she did very little when she was chancellor to clear up concerns about cheating at several dozen schools.

As education historian Diane Ravitch has written, the only thing that the mayoral model of school reform offers is zero accountability:

“What is that model? All decision-making power vested in the office of the mayor, who chooses the school leadership; testing and accountability; report cards for schools with a single letter grade; bonuses for principals whose schools have rising scores; closing schools whose scores do not rise; opening charter schools and small schools; devolving authority to principals to make decisions about spending and instructional programs.”

Perhaps the biggest lesson in the Black debacle is that improving urban education is not done with a single stroke, or with a single dynamic leader or a series of standardized tests. Educating anybody, especially students who live in poverty and often come to class with an array of obstacles to learning, is a complicated endeavor that remains as much art as science. Pretending otherwise will just make things worse.

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