I am trying to sell this school system in a way that's real--not too jazzy," said Robert W. Peebles, Alexandria's superintendent of schools.

But this salesman has jazz in his blood.

And while he's giving his best pitch for urban public school systems his face slowly turns crimson, as it does when he's blowing hard on his clarinet.

Peebles, a soft-spoken, New England educator and former big-band musician, apparently has been playing the right tune the past two years for most parents, School Board members, teachers and city fathers.

After seeing enrollments plunge from 17,000 to 11,000 in the past decade and enduring heart-wrenching school closings and budget battles between the School Board and the City Council, the city seems to be breathing a big sigh of relief as the schools settle down to the key of Peebles.

"In many ways this is the calmest period in the Alexandria schools in the nine years since I have been on the board," said Shirley N. Tyler, Alexandria School Board chairman. "The climate in the whole city has changed towards public schools, and Dr. Peebles goes overboard to help make people understand the system better."

City Manager Douglas Harman, a Rosemont neighbor of Peebles, agrees, saying that under him, "there has been a substantial improvement in the character of the working relationship in the top levels between schools and city government." Harman recently recommended that the City Council fully approve Peebles' school budget for next year.

"I think we've increased credibility," said Peebles, who has held the $59,500-a-year superintendent's position since 1980. "For two years we haven't closed a school, and we are gradually witnessing a more positive feeling about our schools."

Peebles' life is not utopia, however. He faces the wrath of teachers as he prepares to eliminate 27 jobs, and the anger of parents whose children's bus transportation has been cut. He has his share of disagreements with the School Board. And while board member J. Harvey Harrison says he thinks Peebles is off to a good start, he also calls him "too liberal" for his tastes. Moreover, the superintendent is likely to have to deal with the sticky issue of a school closing in the near future.

"We have some tough issues to deal with now," said Peebles. "But in comparison to other places in turmoil, we are relatively stable--and that is a big plus in education."

His big concern is keeping enrollment up and attracting more children to Alexandria schools. "The kids we keep are keeping this a desegregated school system," Peebles said. "Black and white kids are experiencing things together here, and proving that an urban, desegregated school system can work. They can experience the real world every day and still get an education.

"I hate the term white flight, and keeping it out of our schools is worth fighting for. That's why I am willing to go to booster meetings and parents' dinners many nights a week."

The black community generally has good things to say about Peebles. "He is a very sensitive person in regards to the concerns of the black community," said George Lambert, director of the Northern Virginia Branch of the Washington Urban League. "He brings a wealth of knowledge with him and is very responsive."

The superintendent says he's concerned about the "bad rap" that public schools in general have had in the past 15 years. "We are participating in a struggle to win back public support for public schools. We have finally awakened to that, and we have to be more aggressive in it. Public schools cut down on our ability to separate ourselves from each other, and there is strength in that."

Peebles, 56, "a son of Boston and proud of it," was hired in June 1980 from Stamford, Conn., where he headed a system similar to Alexandria's in size and racial makeup. He replaced the sometimes-controversial superintendent John L. Bristol, who resigned to take a higher-paying job as superintendent of an Illinois school system.

"We were looking for someone who would be willing to spend the time and effort to look out for parents' concerns and make contact with the community," said School Board member Judith A. Feaver. "We were also looking for someone who would put time and effort into dealing with the city manager. I have been really pleased with him on both those counts."

There was no such rapport during Bristol's three-year tenure, say city and school officials. Bristol presided over several unpopular school closings aimed at keeping city schools, currently 48 percent black and 41 percent white, racially balanced.

"There was not a close working relationship achieved between the schools and the city government when Dr. Bristol was here," said Harman.

"Bristol was not always able to do things with grace," said Carlyle C. Ring, city councilman and former School Board chairman. "Peebles can work both effectively and decently with people."

"He takes a more enlightened approach to dealing with employe organizations than most other superintendents I have worked with," said Alan Caudill, director of the Education Associaton of Alexandria, which represents 86 percent of city teachers. "And he is never automatically defensive when I walk in his office, like some are."

"He is doing much better than his predecessor in communicating with parents," said Paul Bankerd, Alexandria PTA Council president. "Although there are issues in which some parents have been dissatisfied with him, I do think he is very accessible."

Peebles, who spends many evenings at civic meetings and parent gatherings, was crossing the street in front of his house after a dinner honoring Jesse Jackson last June 6 when he was struck by a car. ("See what I got for working late?" he later joked.) He fractured his left leg and right elbow, and underwent surgery so doctors could insert a pin in his leg. All this came only eight months after triple-bypass heart surgery.

"My first year was just incredible," said Peebles, who spent much of it convalescing. "But I was pleased to find that much support so early in my stay in Alexandria. A lot of people cared and put it into deeds." Second graders sent drawings of Peebles lying on the operating table, and other students sent letters saying, "Sorry your heart's broken."

But Peebles has bounded back. At a staff meeting last summer, just after his doctors told him he could stash the cane he had been using to walk, Peebles sauntered into the meeting wearing a top hat, whistling and twirling the cane.

Peebles grew up outside Boston and later played the clarinet professionally in big bands on Cape Cod. He has a bachelor's degree from Boston University, a master's degree from Harvard University and a doctorate from New York University.

His schedule already leaves him little time to relax with his wife Betty, Peebles says, so he seldom picks up his clarinet, although he says playing it is "very therapeutic." Occasionally he's played in an impromptu jazz group, with board member C. Norman Draper on the drums. And when he's playing, his face turns the same shade of red it does when he's speaking intently to the School Board about budget cuts.

He admits his face is easy to read. "I think I reveal myself too easily, which is not necessarily smart," he observed. Said board member Feaver, "He looks like such a nice guy, but he has been much tougher than he looks."

His days are long. One recent Friday began with an 8 a.m. meeting with Chamber of Commerce members about getting local businesses involved with the schools. Several times during his four-coffee breakfast, Peebles pulled out a crumpled blue piece of paper to jot down ideas to pass on to his staff.

At 9:15, Peebles was at his desk in the school administration building, where a framed poster reads, "Please do not run down, annoy, torment, pester, plague, molest, worry . . . the Superintendent."

That morning he was not to be so lucky. He had to deal with a PTA group clamoring for another reading teacher for its school, parents upset about their children's loss of bus transportation, and an urgent phone call from board chairman Shirley Tyler about a touchy issue before the board.

Then a series of staff meetings. His seven central staff members, who sometimes call themselves and the white-haired Peebles "Snow White and the Seven Dwarfs," say their boss' style is open, warm and easygoing.

He is a meticulous memo reader. "He grades our memos like an English teacher grading papers," said assistant superintendent Mickey Moore. "If there are misplaced modifiers or split infinitives, or if it's filled with educational jargon, he sends it back to us corrected."

During the staff meetings, Peebles pulled out the crumpled blue paper and ticked off points from his breakfast meeting. At 12:30, he drove out of his "Reserved Number One" parking spot to T.C. Williams, Alexandria's only public high school. There he attended a rally and met with students, whose only complaints were about upkeep of the school and lack of a lacrosse team. Out came the now-bedraggled blue paper for a few more notes.

After lunch, Peebles made one of his frequent but unannounced school visits. So far this school year he has made 86 such visits, which he sees as a good way of keeping in touch with what's going on in the classrooms. This time he pulled up to Cora Kelly, an elementary school in Arlandria that was closed from 1976 to 1980 over the protests of many black parents in the area. Some parents still fear the school will be first to close if enrollments continue to drop, but Peebles says he's doing all he can to assuage them.

"I feel very strongly about Cora Kelly," said Peebles. "And it seems that if the board voted to reopen the school, then I should try to do everything I can to keep it that way."

Peebles was delighted to see a fire truck in front of Cora Kelly, and he personally thanked each fireman for showing the first-graders around the truck. "Look at those faces," he said before taking a quick spin around the school. "Don't they just knock you out?"

The visit was like a shot in the arm for the superintendent. "Seeing all those kids together really makes me go," he said, reiterating his belief in urban school systems. "That's what it's all about, and what I'm here for.

"I think I'm different from the average superintendent. Though I felt I wanted a job that did make a difference, I'm not into the fringe benefits of recognition and power."

"And a good thing I'm not," he said with a chuckle as he pulled into the administration building driveway, where the Reserved Number One spot was taken.

Peebles didn't note this on his blue paper, however. It didn't seem to bother him in the least.