The city’s Department of Education exceeded its budget by more than $140 million last year, officials confirmed yesterday when asked by The New York Sun.

The director of the city’s Office of Management and Budget, Mark Page, said about 40% of that was due to unanticipated costs for special education, while about 60% was due to what he called an “accounting realignment” related to the mayor’s takeover of the public school system.

The overrun might seem small relative to the education department’s total budget of $12.5 billion, but in the tight spending environment that exists in the school system, teachers, principals, and central administrators were exultant over the extra $288 million that Albany granted the department in August.

“One-hundred-forty-two million may be no big deal when it comes to a $13 billion budget, but if you tell any of the schools that have gotten cuts that it’s not a big deal, they’d look at you as if you’d lost your mind,” the teachers union president, Randi Weingarten, said.

The figure is also meaningful when taken in the context of Mayor Bloomberg’s announcement Friday that city agencies, with the exception of the education department, would have to cut $900 million in spending over the next 20 months.

Sources said the gap between the department’s resources and its spending level was larger than in past years. Indeed, last year the department recorded a surplus of $30 million at the end of the school year.

Mr. Page, however, said the 2003-04 overrun is not significant in the grand scheme of things.

“The bulk of the difference is because of bringing the spending and revenue treatment of the department’s operations much more exactly in line with the standards that govern the city’s main budget and accounting system,” he said. “It’s actually evidence of positive progress we’ve been able to make.”

He said that line by line on the budget for the last school year, the education department spent $236 million more than it had, but it also under-spent on some items. After the June 30 end of the fiscal year, when the city subtracted the amount of money it had saved on other budget lines, the $236 million figure dropped to $155 million.

“If I have a certain amount of money that’s authorized for pencils, and I don’t spend all the money on pencils but I run over on chalk, the budget system is going to say that I have an overage in terms of my chalk authorization,” Mr. Page explained. “That’s going to show up as a deficit. But when I get to the end, and I’m trying to make the two sides balance, as a practical matter the unspent resources, pencils, have moved over to cover the chalk.”

The gap narrowed by another $13 million, he said, when unexpected revenues – from sources such as rentals of school auditoriums – were subtracted.

Of the remaining $142 million in overspending, Mr. Page said, about $60 million was spent on special-ed expenses, which department officials “have no control over.” For example, he said, more students than expected might have been referred for special services.

The rest of the overrun resulted from the synchronization of the old budgeting and accounting system the education department used before mayoral control of the school system. He said the resulting sum was a “onetime cost” and that he “wouldn’t expect a similar scale of adjustments in the future.”

Mr. Page said there were hundreds of millions of dollars worth of adjustments across the different agency budgets since June. Overall, he said, the city expected to post a surplus of $5 million.

The head of the United Federation of Teachers, Ms. Weingarten, questioned the unexpected special-ed costs.

“Something’s going on,” she said. Before the special-ed system was overhauled by Mr. Bloomberg’s chancellor, Joel Klein, last year, “you didn’t have these unexpected special-ed costs,” the union president said.

She said someone should inspect the education department’s finances to see what is actually going on and to figure out what could be done more efficiently next year.

The City Council member who heads its Committee on Education, Eva Moskowitz of Manhattan, said, “Going over budget is not a good thing.” Ms. Moskowitz said, however, that she’s more concerned that the figures show the school system is becoming “increasingly centralized,” something she doesn’t think is good for students.

“We all have to learn to live within our means,” she said. “But more importantly, all this talk about money getting to the schools seems to be somewhat belied by the fact that central’s budget has mushroomed.”

She added that the $142 million overrun was much larger than the anticipated $15 million overrun the department testified about last spring before the council committee.

A Manhattan Institute budget expert, E.J. McMahon, said he couldn’t really understand the overruns without more detailed information, but he said even the 1.1% overrun was “pretty significant.”