At least half a dozen major city school districts are combing the country for new superintendents — and they’re frequently looking to administrators who cut their teeth working under former New York City Schools Chancellor Joel Klein.

Boston, Newark, Chicago, New Orleans, and Atlanta are all looking for new superintendents, and Providence, R.I., just lost its leader. Deputy Chancellor John White was floated as a candidate in Chicago and is under consideration in other districts, including New Orleans, according to sources familiar with the searches. Districts have also eyed Jean-Claude Brizard, the Rochester, N.Y., superintendent who once worked for Klein, and Andres Alonso, another Klein deputy who now runs the Baltimore public schools.

“As far as I know, they’re all being recruited in multiple venues right now,” Klein said today in a phone interview. “Who knows where the music will all stop.”

The hunts for talent have high stakes for the community of education entrepreneurs that we’ve called “idealocrats.” On one hand, these reformers argue that the next frontier in their battle is to transform not just a school or a set of schools but an entire school district. Yet the same people regularly point out that there is a limited pool of people who are both ready and willing to take on this challenge.

“People are looking for people who have the credibility to speak to the classroom question but also have the leadership capacity that too often isn’t really sought in the education space,” said one person familiar with the searches. “Cities are not willing to compromise on a kind of institutional person. And yet you’re talking about paying people … to go out and take a beating every night.”