Midnight, June 30, 2009. Mark the date. At that moment control over New York’s public schools will almost assuredly be removed from the office of the mayor.

That’s the opinion of Diane Ravitch, a scholar who has devoted decades to the study of the history of Gotham’s school system. Her famous book on the subject, “The Great School Wars,” was first published during the time that centralized control of the schools was supplanted by decentralized community control.

A generation later, the decentralized system, crafted by the best and brightest of their day, backed by well-heeled foundations and well-meaning souls in the business community, has given way once again to mayoral control.

The same do-gooders that led Mayor Lindsay into decentralization are now whispering their latest ideas, such as the troubled small-school initiative, into the ears of Mayor Bloomberg and Chancellor Klein. The more things change, the more they stay the same.

With the perspective afforded by her knowledge of history, Ms. Ravitch knows that the only thing certain is change. And in this case, change is written into the law. The legislation that handed Mr. Bloomberg control of the schools in 2002 has a sunset provision that expires in the midst of the mayoral campaign of 2009.

The alignment of the sun, moon, and planets that permitted Mr. Bloomberg to win control no longer exists. Both the majority Democrats in the Assembly and the majority Republicans in the Senate have expressed misgivings with the top down structure that the mayor has put in place. To end mayoral control of the schools five years from now, the Legislature merely has to do nothing – something that appears to come naturally to them.

At a forum at Baruch College Tuesday, Ms. Ravitch predicted that the current structure will indeed be allowed to expire. “It’s too much power concentrated in one person…I don’t think it [mayoral control] will survive Mayor Bloomberg.”

Ms. Ravitch, although a supporter of Mr. Bloomberg’s re-election, believes that the mayor has been insensitive to the needs of a public that demands input on educational issues, asserting that “there is no place to have your voice heard beyond your local school,”

The mayor’s emasculation of the Panel for Educational Policy, intended to be a forum for discussion of school matters when created by the Legislature, has already come back to haunt him. When he fired a number of panel members to ensure victory on the vote “ending” social promotion, Mr. Bloomberg was cheered by editorial boards that agreed with his position. I wonder whether they will be so enthusiastic if a future mayor – perhaps an unreconstructed liberal such as Fernando Ferrer – exerts this control to take the system in an opposite direction?

The unintended consequence of term limits is that no matter how well Mr. Bloomberg runs the schools, at best he will be a lame duck when the current law expires. In the midst of the election season, which political party will be willing to cede to the other the unfettered control of thousand of jobs paying in excess of $100,000 a year? It is politics that will doom the current structure.

The dark side of mayoral control is that the potential exists for the mixing of politics and the schools. This is what may well be happening with the commission set up by the City Council speaker Gifford Miller to monitor compliance with the Campaign for Fiscal Equity lawsuit. On Wednesday, Mr. Miller named former chancellor Anthony Alvarado as the executive director of the panel.

Mr. Alvarado has become an educational icon since he was forced to resign as chancellor following a bizarre scandal involving his personal finances in 1984. He rehabilitated himself during a stint as Superintendent of Manhattan’s District 2, where he cleverly developed programs that raised test scores by luring upper middle-class students back to his schools. This led to a lucrative stint as the deputy superintendent for instruction in San Diego’s public schools.

There is a message in this. Mr. Miller, a likely candidate for mayor next year, is letting the public know that he has an educational team in place, led by Mr. Alvarado.

There is irony in this. Mr. Klein was quick to make a pilgrimage to San Diego after being named chancellor. The administration’s “Children First” initiative mirrors the “Blueprint for Success” program set up by Mr. Alvarado and his boss in San Diego, Alan Bersin, who like Mr. Klein is a former prosecutor.

Shortly after Mr. Klein put the program cloned from San Diego into place, Mr. Alvarado was dismissed from his job. Test scores were flat in San Diego, and Mr. Alvarado’s fondness for huge expenditures for teacher training were said to have bankrupted the system.

Like our model on the left coast, scores in New York are flat, and the city’s school budget is in such disarray that on Wednesday the Daily News charged that it would take a forensic accountant to untangle the system’s finances.

If Mr. Miller depends on the programs of Mr. Alvarado to justify his mayoral bid, it won’t be surprising to see more critics like Ms. Ravitch cast their lot with the mayor. They will count on the inevitable march of time to cure the ills created by mayoral control.