The principal of a middle school in this large coastal city had been asked several times to take the principal's job at 4,700-student Long Beach Polytechnic High School. Repeatedly, he had said no.

Then one day, while out talking to students, he heard on his walkie-talkie that there was an unscheduled visitor in his office, Long Beach Superintendent Carl A. Cohn. He greeted the smiling, well-dressed Cohn with the same polite refusal. He didn't want to go to Long Beach Poly.

Cohn's smile only got bigger. "Well, that's very interesting," the superintendent told Principal Shawn Ashley, "but we don't always get what we want in life, do we, Shawn."

And so Ashley soon found himself at the big high school, enjoying the job in spite of himself and shaking his head, as many other Long Beach educators have done, at Cohn's persistence and focus.

Last week, Mayor Anthony A. Williams (D) and other top District officials identified Cohn as their first choice to become the next D.C. school superintendent, after flying 2,700 miles to California to woo him. Although he has not decided whether to come to Washington, the 58-year-old professor already has had an impact in the city: During a private breakfast with Williams, he persuaded the mayor to drop his high-profile campaign to win direct control of D.C. schools.

Educators, parents and public officials in Long Beach, the state's third-largest school district, said Cohn is well worth the attention that D.C. leaders are lavishing on him.

During 10 years as Long Beach superintendent, they said, Cohn sparked major improvement in the district with such initiatives as school uniforms for students up to eighth grade, new reading requirements for third-graders and some single-sex classes. He raised test scores significantly and is credited with improving student attendance, lowering suspension and dropout rates and raising the number of college-prep classes.

Still, many analysts wonder whether Cohn can succeed in the District, where low student achievement and political battles between the school system's overseers -- including the mayor, the D.C. Council, the school board and Congress -- have made the superintendency one of the most difficult assignments in American education.

"We know that visionary leadership that is allowed to be implemented absolutely can improve beleaguered school districts," said Ross Wiener, policy director of the Washington-based nonprofit group, The Education Trust, who admires Cohn's accomplishments.

"But a superintendent cannot be expected to be an ombudsman or referee for the fractured debates over governance and control that you find in this city."

Several previous D.C. superintendents arrived promising bold changes, only to be frustrated by political bickering and by the scope of the school system's academic, financial and personnel problems. In particular, they found that tackling dysfunction in the most basic administrative operations, such as payroll and budgeting, often prevented them from focusing on improvements in classroom teaching and learning.

Cohn retired as Long Beach superintendent in 2002 to be a professor at the University of Southern California's education school, saying he was through with the stresses of running a big urban district. So Long Beach friends were surprised when he showed interest in the D.C. job. Cohn said he is talking to his family about the possible move and asking many school experts in the District and elsewhere just how difficult they think it would be to fix the city's schools.

Those who have worked with him said that although Cohn would have to deal with a more divided political community in Washington, his record in Long Beach shows that he can be tenacious in fighting for his ideas.

"He's not afraid to take risks," said Clarence Rhone, a coach at Long Beach Poly. "He's not afraid to step on people's toes."

When Cohn learned of bureaucrats who were trying to block his initiatives, he would be quick to call them in for a long talk, Long Beach educators said. That reputation was helpful to principals, Ashley recalled. When their reforms ran into resistance from someone at school headquarters, he said, they often could get their way by asking: "What do you think the superintendent meant when he said our schools come first? Could you explain that to me, sir?"

In an interview Friday, two days after being assured by D.C. leaders that he had their full support, Cohn said his style is not to give up when he finds opposition to his policies, but to work harder to show possible benefits.

He said that if he went to the District and found "that people wanted to stay stuck on adult governance issues rather than the laser-like focus on improving the schools, I would be the first to let everyone know they were not delivering on their promise."

He also said that if he takes the D.C. job, he will move all necessary resources to the elementary schools to make sure all children are reading by third grade. That emphasis worked in Long Beach and appears to be having an impact in such Washington area districts as Montgomery County, but it can cause turf battles as teachers and principals at other grade levels feel slighted. Cohn said he will not stand for such infighting.

National education analysts said Cohn is the rare urban superintendent who left his job with a better reputation than when he started. During his tenure, for example, the reading scores of Long Beach second-graders rose from the 25th percentile in 1993 to the 52nd percentile in 2001.

"Carl Cohn is a super thoughtful and refreshingly candid leader," said Bruce Fuller, professor of education and public policy at the University of California at Berkeley. "He listens intently and acts carefully."

But he did not please everyone in Long Beach. Jim Deaton, executive director of the Teachers Association of Long Beach, said he admired Cohn's charm and political skills, but when it came to rewarding teachers for their students' increases in achievement, "he didn't deliver."

Cohn fought with residents who did not want a special school for failing eighth-graders in their neighborhood. He clashed with another community that wanted its own school district. And although his requirement for school uniforms was supported by most parents, some tried unsuccessfully to block it in court.

Some local politicians objected to Cohn's habit of endorsing candidates for the school board, a very unusual practice for an appointed superintendent.

Cohn was born and raised in Long Beach, the fifth of six children. He never spent a day in a public school, attending Catholic schools throughout his childhood and graduating from St. John's College in Camarillo, Calif.

He is married to Kathleen Carmichael, who is associate vice president for academic personnel at California State University, Long Beach. Their son and daughter attended Long Beach public schools.

Cohn has spent most of his career in California. After jobs as a social studies teacher and counselor at high schools in Compton and Long Beach, he taught education at the University of Pittsburgh in 1984 and then took a similar job at Cal State-Los Angeles in 1986.

Two years later, he returned to the Long Beach schools as director of attendance. He became an area superintendent in 1990 and was named superintendent of the district in 1992.

That year, Long Beach had 76,000 students. It has since grown to 97,000, with a massive inflow of Hispanic families and some students returning from private schools. D.C. enrollment, not counting public charter schools, has dropped to 64,200.

The situation in Long Beach was not good when Cohn took charge, although experts said test scores and morale were never as low as they are in the District.

The weak California economy had forced a $20 million cut in the Long Beach school budget. There were drugs and gangs and concern over the growing number of students who could not speak English.

But the five members of the Long Beach school board found that Cohn's open managerial style was what they had hoped for. Mary Stanton, a former teacher elected to the board in 1990, said, "He created the feeling that we were a team, all in this together, and he and the staff were open to us at any time, which had not been the case before."

Every three months, Cohn held two- or three-day public workshops with the board, during which board members would discuss their ideas for change.

The board also evaluated Cohn's performance every quarter in a 90-minute private session. Most superintendents are evaluated by their board once a year, but Cohn said that the Long Beach system helped keep him and his board united and that he would like to use the same system with the District's nine-member board.

Some who've watched Cohn in Long Beach said they are concerned about how he would perform with the larger, more fractured D.C. school board. Stanton, although acknowledging the difference in the cities, said if anyone could make positive change in the District schools, it would be Cohn.

"It was probably easier than D.C. because we were all behind him," she said, "but he has a very forceful personality, and he does his homework. I don't think he is a quitter, and he has a passion for what he is doing, which you have to have. It is a challenge, and he likes to take on challenges."

Carl A. Cohn spent 10 years as superintendent before he became a college professor.Carl A. Cohn, former superintendent of schools in Long Beach, Calif., is District officials' top choice to lead the D.C. school system.