5:04 p.m. | Updated The students at Williamsburg Charter High School in Brooklyn are taught how to conjugate Latin verbs, analyze Shakespeare sonnets and decipher Arthur Miller plays. This year, they also learned how to wrangle in State Supreme Court for survival, a lesson that culminated on Thursday with news that the eight-year-old charter school, adored by students but slated by the Department of Education to be closed, will stay open.

In her ruling, Judge Ellen M. Spodek of State Supreme Court in Brooklyn wrote that the city's decision this year to revoke the school's charter, despite having renewed it in 2009, was "arbitrary and capricious" and "not corroborated by any policy, regulation or protocol established by the D.O.E."

She said the charter's revocation was now "vacated," a decision that will keep the school open at least until 2014, when the charter is again up for renewal.

Kyle Spencer Soon-to-be graduates of Williamsburg Charter High School learn at their graduation Thursday evening that their school has been spared from closing.

The decision came 11 days after classes at the school had ended, and within hours of the school's fifth graduation, an event that had promised to be bittersweet.

Students, parents and administrators have been waiting for weeks to hear whether the school would exist in the fall, with many students reluctantly enrolling elsewhere to make sure they had a slot for September.

Asked about the ruling, the city’s attorney, Andrew Rauchberg, said: "We disagree with the decision and plan to pursue an appeal."

In an e-mail, Patrick Kern, an administrator at the school, declared the ruling "monumental," and said it would set a precedent for other charter school closing cases.

"It's been a long fight here," said Joseph Cardarelli, the school's director of accountability and compliance. "We are all just elated."

In announcing in January that it wanted to shut the school, the Education Department cited management and financial issues and said the school's charter was invalid. The school, which includes grades 9 through 12, has about 870 students and received a C on its latest progress report.

Its founder, Eddie Calderon-Melendez, 48, has been indicted on charges of failing to pay $70,000 in city and state taxes and taking money from the school for his own use, including during a trip to Europe. He has since been fired as the chief executive.

The school has also suffered financially in recent years because of the delayed renovation of its new building, which administrators moved into in 2010, a year later than expected.

The court ruling, Mr. Cardarelli said, supported several of the school's claims that parents were denied a right to a public meeting about the closing and that the Education Department's issues with the school's charter should have been addressed in 2009 when the city renewed it.

School officials have also argued that the school was performing well, and it should not be penalized now for any actions by Mr. Calderon-Melendez.

In addition to Williamsburg Charter, Mr. Calderon-Melendez started the Believe School Network and opened two other schools under it: Believe Northside and Believe Southside. Both were also slated in January to close at the end of this year. But administrators at the Northside School fought the closing, and the city is permitting the school to stay open.

State investigators say they became increasingly concerned about Mr. Calderon-Melendez last year, when they asked him to produce personal tax returns. What he came up with, they say, were documents he had had employees fabricate.

According to court documents, financial mishandling was just one of the many reasons the city sought to shutter Williamsburg Charter. In 2009, the school moved to secure a loan that the city says violated state charter school law. And when the city moved ahead to put the school on a list of charters that were at risk for closing, city officials did not think the school moved fast enough to remedy the considerable concerns about the board’s make-up and the school’s relationship with Mr. Calderon-Melendez.

But Judge Spodek found that city officials were partially to blame and knew about at least some of the school’s managerial problems before they chose to renew the school’s charter in 2009. City officials, the ruling states, were guilty of “ineffectively handling their responsibilities.”

At Williamsburg Charter, where leaf-green blazers and crisp white oxfords are required and the curriculum strives to emulate offerings at city private schools, students did not sit on the sidelines during this recent tussle to preserve their school. They cheered at court hearings, organized rallies as part of a class on government and participation, and collected 3,000 signatures from bodegas and fast-food restaurants around the school’s neighborhood.

They also solicited names from members of their Brooklyn churches and wrote hundreds of letters that became exhibits in the case. In some of the letters, students referred to the school, which has a rock-climbing wall, a kiln in the art room and a state-of-the-art theater with professional-grade lighting, as their “second home.”

“They learned a lot about civic participation,” said Mr. Cardarelli.

On Thursday, he and other officials at the school prepared to inform parents about the news by setting up the school’s automatic phone call system, most often used to let parents know about absences.

As for the school’s 171 graduating seniors, he said he believed many would learn about the ruling at the ceremony, which was scheduled to start at 6 p.m.