NEW YORK — The city’s school chancellor resigned yesterday after three difficult months on the job, a defeat for Mayor Michael Bloomberg and his decision to install a publishing executive with no experience as an educator to lead the nation’s largest public school system.
In her brief stint as chancellor, Cathie Black had faced heckling by parents, the departure of several deputy chancellors, and scorn over her joke that school overcrowding could be fixed with birth control.
Bloomberg announced the resignation only days after a poll showed her approval rating had dropped to 17 percent. He named Deputy Mayor Dennis Walcott to replace her.
Bloomberg said at a City Hall news conference that he and Black met yesterday morning and “mutually agreed that it is in the city’s best interest if she steps down as chancellor.’’
“We both agreed that the story had become her and it should be about the students,’’ said Bloomberg. Black did not attend the news conference.
The mayor’s appointment of the former Hearst Magazines chairwoman has proven to be one of the deepest embarrassments of Bloomberg’s nine years in office.
Her selection was a surprise even to some officials within the administration, and critics said it had been secretive. No formal search had been announced before Black was appointed.
“I will take full responsibility for the fact that this has not worked out as either of us had hoped or expected,’’ said the mayor, known as a fierce defender of his administration’s top appointments.