The city’s Independent Budget Office will release portions of a report today that indicate the Department of Education has saved tens of millions of dollars less than originally announced after its reorganization under Mayor Bloomberg’s Children First program, The New York Sun was told yesterday.

For months, Schools Chancellor Joel Klein has been speaking with pride of $267 million he said he had whittled out of the department’s bloated budget between 2002 and 2004.

Those figures have been hotly contested.

Last month, in a letter to the schools chief obtained by the Sun, the city comptroller, William Thompson Jr., said his auditors calculated the savings as more in the neighborhood of $140 million. The education department said it stood by its numbers.

Now the IBO has weighed in with its own analysis, which puts the savings between $191 million and $221 million over the same period – roughly halfway between the figures of the chancellor and the comptroller.

The new report would be just another instance of quibbling over figures if it weren’t an election year and if Mr. Bloomberg had not made his overhaul of the Department of Education a key plank in his platform for re-election.

Using additional information provided by the education department, the Independent Budget Office figured the department’s administrative spending fell by $221 million from 2002 to 2004. In computing the figure used by Mr. Klein, however, the department didn’t include the savings in fringe benefits from the reorganization, officials of the budget office said.

If the watchdog agency did the math the same way the department did – ignoring $31 million in fringe-benefit savings realized by closing district offices, by offering buyouts, and through some attrition – then the saving would be even lower, $191 million, the report says.

In a letter to Mr. Klein last month, Mr. Thompson complained that his auditors had difficulty following the precise savings achieved by the department and tracking whether the money ended up back in the classroom, as the Bloomberg administration has claimed.

The budget office, in its new report, expressed similar concern, saying: “It is difficult to determine whether the savings were shifted to the classroom as claimed by the Chancellor and the Mayor. Instructional spending has increased by over $1 billion over the same period, but there is no way to determine how much of that increase would have occurred even if the department had not achieved significant administrative savings.”

The comptroller’s aides, for their part, found that of the $140 million in achieved savings they identified, only $4 million could be attributed directly to cost-cutting at department headquarters. Further, the analysts found no evidence that the savings ended up in new spending in classrooms, as the department has assured parents.

The comptroller’s office alerted Mr. Klein early last year to what it called the tracking problems in department accounting, and, according to a letter obtained by the Sun last month, Mr. Thompson asked the chancellor in July to discuss how the department was keeping its books.

The department has not responded to Mr. Thompson’s request, a spokesman from the comptroller’s office, Jeff Simmons, told the Sun.