The people who have worked with Robert W. Peebles, Alexandria's incoming school superintendent, tend to remember two kinds of things about him: i

He is a "personable guy" who loves the Boston Red Sox, the jazz clarinet and reorganizing a large and previously unchecked school system.

At the same time, his critics and even some supporters say, he made little progress in increasing the number of black teachers and administrators in the Stamford, Conn., schools, where he has been superintendent for the last five years and where a third of the enrollment is black.

"He had good concepts and he was sensitive to black concerns, but he could have taken a stronger stand on affirmative action and the number of black personnel in the school system," said Gilbert Rozier, executive director of the Urban League of Southwestern Fairfield County (Conn.), which includes Stamford.

"I don't know what the hell we're going to do without him," countered Otto Calder, vice chairman of the Stamford Board of Education. "He is a very able and knowledgeable educator. I've never met anyone more empathetic to the needs of minority people than Bob Peebles."

Peebles, 54, comes to a school system that bears many similarities to the one he is leaving. Both Alexandria and Stamford have large minority populations, budget-conscious polititians, declining enrollments and increasing costs.

According to some school board observers in Alexandria, Peebles' performance in Stamford may indicate his plans in his new post. In Conneticut, he took a sharp look at the school curriculum (primarily streamlining and establishing schoolwide goals), skirted a potentially troublesome racial discrimination lawsuit and used a "magnet school" concept to attract white students to a predominantly black elementary school.

Despite the similarities, Peebles left a far more complex racial and political system in the city 30 miles outside Manhattan that the one he will face in the city inside the Beltway.

Peebles, who gets a slight pay increase in the $55,000 a year Alexandria job, left behind a school system now being scrutinized by the U.S. Economic Enployment Opportunities Commission, as well as the U.S. Department of Education because of allegedly poor minority hiring and promotion practices.

The Connecticut School system has 16,000 students about 37 percent of whom are classed as minority students. But no more than 10 percent of its teachers and administrators are members of a minority groups.

Although Peebles brought in Stamford's first black high school principal, he effected little, if any, gain in the overall percentage of black professional personnel, critics said.

(By contrast, the Alexandria school system is not under any known federal inquiry. And the numbers themselves are different: The Alexandria system has about 11,000 students, with a 48 percent minority enrollment. About 31 percent of the teacher-administrative personnel are minorities.)

In Stamford, a black administrator, Nellie Spears, filed a federal lawsuit against the school system several years ago, claiming she had been discriminated against in hiring and promotion because she is black. The case was settled out of court, but last January the NAACP complained to federal officials about the alleged practices -- complaints which are still pending, local officials said.

"I wish we had taken that case to court," Peebles said this week. "Then the facts of the case could have come out. We could have done better with our affirmative action program, but we've been handicapped by declining enrollments, reduction in the work force and contracts that emphasize senority. That's an excuse, but it's also a reality."

In working to address problems of racial imbalance among students, Peebles developed a plan for an elementary school two years ago. The school, Peebles said, was nearly 90 percent black and drastically out of line with the Stamford's own guidelines for its voluntarily desegregated schools.

Peebles developed a "magnet school" to attract white students, thus avoiding the possibility of closing the school.

The only students eligible to take the special program were black students already at the school or white students willing to attend classes there voluntarily.

"We created a nearly 50/50 racial mix nearly overnight," said Stamford school board member Adele Gordon.

Peebles said such a concept might work in Alexandria, though he added that he had no idea whether he would ever recommend it. Peebles' predecessor in Alexandria, John L. Bristol, has been criticized by black school board members for closing two schools in black neighborhoods because of declining enrollment. The magnet school concept might serve as an alternative to school closings if that situation ever arises again, several people said.

Peebles wins the higest praise for his ability to work with staff and teachers and for his reorganization of the burdensome and often confusing bureaucracy of the Stamford school system.

Peebles wowed some Alexandria administrators last week with his own brand of low-keyed folksiness, leaving his audience refreshingly delighted.

"He's been very good, thorough and professional with us at budget time," said Margaret Nolan, chairman of the Stamford Board of Finance, one of two elected political bodies which oversee the school system.

"I'm very pleased with what Bob has done," said Stamford school board member Gordon. "We now evaluate programs and personnel, which we never did before.

"He was admittedly weak on finances when he first arrived, but he made himself knowledgeable about it. We made tremendous strides in format, organization and presentation because of him."

The Stamford school budget is currently about $41 million, nearly the same as the current Alexandria budget of about $41 million.

Peebles holds a doctorate from New York University, a master's degree from Harvard and a bachelor's degree from Boston University. He will initially serve a one-year term, filling out the remainder of Bristol's four-year contract, then is expected to sign a four-year contract of his own.

Peebles has two grown children and a teen-aged daughter who will finish high school in Stamford. An avid jazz clarinetist, he refused to say if he would ever interrupt an Alexandria board meeting as he did in Stamford to join a nearby jazz combo.

One thing he is clear on:

"I'll never leave the Red Sox. We're gone through too many heartbreaks together.