The ed. pool: Staff bet on Black for ax

Weeks before Mayor Bloomberg pulled the rug from under the epic disaster known as Cathie Black, a ghoul pool was launched in the halls of city government. To win, one had to accurately answer this:

When do you expect the volatile mayor to get fed up with his incompetent, dilettante schools chancellor and thrust her, headfirst, under the bus?

It happened Thursday.

“People were asking, ‘Did you win the pool?’ ” laughed a government source, who said Black’s sudden demise came even earlier than bettors expected. “People knew it was the beginning of the end.”

In fact, were it not for the mayor’s stubborn reluctance to admit he made a whopper of a mistake, Black, the only person on planet Earth surprised by her ouster, may not have lasted as long as she did.

In 96 days — the average length of a Britney Spears marriage — Black went from a talented manager and Bloomberg party guest to a dame whose very existence aggravated parents, teachers, her own scattering lieutenants and, fatally, Bloomberg staffers.

Even Bloomberg’s close aide, Deputy Mayor Howard Wolfson, learned of Black’s hiring a mere half-hour before the mayor announced it last November.

She should have seen it coming. But a clueless Black was so blind to reality, she whined on the way out the door that her education career was felled by . . . wait for it . . . sexism!

“If I were a guy, would I have had the pounding that I did?” she railed to Fortune magazine on Friday. Truth is, sources told me, the very maneuver to which Black still clings — blame sex! — had been tried by the administration, then abandoned.

“The strategy was to get sympathetic female columnists to write that Black was getting judged by a harsher measure because she’s a woman,” said a source. “That tactic didn’t work.”

Black failed to notice that she was on Mayor Bloomberg’s “countdown clock,” as one staffer put it. The clock started ticking with Black’s first gaffe — when she cracked in January, two weeks into the job, that “some birth control for a while” is the solution to school overcrowding, then followed that zinger with a barb about having to make “Sophie’s Choices” in school cuts. Essentially, she joked that her job was to choose which kid is to be murdered to save another.

“Once you become a liability, [the mayor] distances himself from you,” said the source. Black hung on. Until two events spelled her doom.

The first was a NY1/Marist poll last Monday that gave Black an approval rating of 17 percent — making her less likeable than Snooki. The mayor’s reaction: silence.

He “didn’t push back on the poll numbers,” said the source. “No one argued that the numbers were inaccurate. They never bothered to find a third party to say, ‘She’s got the skills. Give her a chance.’ Those numbers gave them cover.”

Two days later, Black lost Deputy Chancellor John White to a school district in New Orleans, of all places. He was the second loss in a week and the fourth altogether. “That kind of brain drain is not what we need,” the source said. “Joel [Klein, the former chancellor] had a great team that’s coming apart, piece by piece.”

As even school custodians knew, it was time for Bloomberg to cut his losses. Now Cathie Black has devolved into a punch line. A cautionary tale that — astonishingly — Bloomberg seems to be repeating.

Bloomberg brought in Deputy Mayor Dennis Walcott to clean the mess. Compared to Black’s rich-gal cred and prickly personality, Walcott is a likeable public-school grad who worked briefly as a teacher and still beds down in Queens. But . . .

“He knows the system. He knows where the men’s room is. But he’s not a manager,” groused one City Hall source. “So the system will continue to be mismanaged.”

Others are amazed the mayor didn’t conduct a national search, used to find school chiefs in tiny hamlets in lesser states, like New Jersey.

“He looked over his shoulder and saw Walcott,” said a second City Hall veteran. “At least he didn’t look across the room at a cocktail party, as he did when he found Black.”

At least, as Black put it, she’ll return to her roots — doing lunch at overpriced Michael’s, wearing designer duds and escaping “the worst pictures!”

Our nightmare is over.

Queensboro off-ramp smash-ups no accident

The accident was a freaky, one-time occurrence. Then, it happened again.

Two cars, nine days apart, crashed off the exit ramp of the Queensboro Bridge, smashing into the same Long Island City store fronts. The first smash-up killed a pedestrian and severed the driver’s arm. The driver in the second crash also lost his arm. His passenger died.

A city Transportation Department spokesmouth blamed the carnage on excessive speed. But he failed to stress that bridge exit ramps had been altered dangerously in January — to make them more pedestrian-friendly. (Tell that to Anthony Buscemi, struck and killed as he strolled on a sidewalk near the bridge.) To that end, the city added a park, planters and, you guessed it, a bike path.

Does this have to happen a third time before someone stops the madness?

Bam’s high price of paying tribute

Live long enough, you’ll see everything. President Obama traveled to New York last week to kiss the ring of Al Sharpton. Bill from Massachusetts writes:

“Unbelievable. This ‘rev’ has been in jail [for protesting Navy bombing exercises on the Puerto Rican Island of Vieques], owes money to the IRS [he’s claimed the government wants to intimidate him], was the ring leader in the Tawana Brawley” rape hoax. “And our president flies to New York to pay tribute? This country is going down the drain.”

Obama once dismissed Sharpton as divisive. Now he’ll sell his soul in exchange for help delivering the minority vote.

When did leadership get so cheap?

KATIE’S BLAME GAME