HAS SCHOOLS Superintendent Arlene Ackerman blundered her way into losing her strongest ally in her fight for school funding?

It sure looks that way. Sources said Mayor Nutter spent the weekend fuming after Ackerman kept him out of the loop on her deal to preserve full-day kindergarten with federal funding.

"I think before this incident he certainly tried to seem supportive, and now he looks foolish in front of the rest of the city," said Zack Stalberg, president of the watchdog group Committee of Seventy. "I think if they've got anything of a relationship at this point, it would surprise me."

Political insiders agree that the past few days have been a blow for Nutter, who has been aggressively lobbying city and state officials for more money for the school district, which faces a $629 million funding gap for the fiscal year that starts July 1.

Not only was Nutter left out in the cold Friday when Ackerman announced her big save, but she robbed him of his best argument for ponying up more cash - restoring full-day kindergarten - and reinforced the criticism that the district's books deserve more review.

"It presents more of a challenge to the mayor," said City Councilman Darrell Clarke. "There was tepid support at best for those proposals early on ... and with this latest measure as it relates to full-day kindergarten that could have diminished whatever support [the proposed tax hikes] had."

What happens next is anyone's guess. Nutter has demanded more budget accountability from the district and heads to Harrisburg today to continue to lobby for more money. He met with some Council members privately yesterday to continue his pressure on them to enact tax increases to provide up to $110 million to the district.

Nutter, who in April described himself as a "very strong supporter of the superintendent," chose his words carefully yesterday when asked if he would back Ackerman after the budget crisis was resolved.

"One, I don't know why you're asking the question," Nutter said. "All of us are very focused on making sure the young people get the high-quality education they need. That's what I'm focused on at the moment."

District spokeswoman Shana Kemp said the relationship between Ackerman and Nutter was "fine."

"There was no effort to undercut any efforts he's been making toward full-day kindergarten," Kemp said. "We believe that the mayor is just as dedicated to ensuring the success of young people in this city as Dr. Ackerman is, and they will continue to work together."

Ackerman told the Inquirer that she had "good intentions" and was "sorry for whatever embarrassment this caused for the mayor." She didn't return a late call from the Daily News.

Meanwhile, Council members said there was no consensus on any proposals. Councilwoman Marian Tasco said they want Ackerman back to talk details.

"We were certainly surprised when we received the notice that full-day kindergarten was funded," Tasco said. "Where is that money coming from? Are you robbing Peter to pay Paul?"

Nutter has proposed a tax of 2 cents per ounce on sugary drinks and a 10 percent property-tax hike as ways to fix the budget problem.

Alternate proposals include Clarke's pitch that the city temporarily raise the property tax to generate $44 million, which would be doled out from a grant fund. And Councilman Bill Green yesterday said he thought the problem could be solved through further cuts and by tapping the projected $50 million year-end fund balance in next year's city budget.

Finance Director Rob Dubow questioned touching the fund balance, which is the city's main financial insurance. This year, the city was expected to end the year with a $13 million balance, but will instead finish with $5 million because of unplanned costs, such as snow removal.