She has been described as a peacemaker and "the conscience" of the Prince George's school board. But just as often in her seven years on the board, Bonnie F. Johns has found herself alone against her colleagues as the county grappled with the divisive issues of busing, desegregation and school closings.

Johns -- one of two black board members in a county whose schools are more than 50 percent black -- is retiring following a turbulent tenure in which for many blacks she has been a powerful voice.

"Many times I have been a vote of one. It's pressure. It's stress, but it's not so difficult that I had any problem voting my conscience, because I saw the issues very clearly," she said. "It's like being the only black. All eyes, all questions, all pressures are on you."

Johns, 54, says she is quitting the board out of a desire to leave the fray and pull back from the demands of the job.

"I just don't want to keep on at this pace," she said in a recent interview. "These have been some very difficult years."

For the past year, as board chairwoman, Johns has been placed in the even more uncomfortable position of representing actions she often personally rejects. The year has capped a tenure marked by similar conflicts, through which Johns has repeatedly fought -- often by herself -- moves to reduce busing and alter a court-ordered desegregation plan.

She was appointed in 1977 to fill a vacant seat, and until Sarah J. Johnson was appointed five years later, Johns was the only black on the school board. She represents the predominantly black 6th District on the board, which she joined when it was still composed of several members elected on antibusing platforms.

In her first year, Johns opposed a move to reduce busing and increase the number of children in neighborhood schools. The following year, she opposed two similar plans. In 1979, she was the only member to vote against appointment of a citizens advisory committee to find ways to reduce busing. And in 1980, she was the only member to vote against a reduction in busing that altered the 1972 court-ordered desegregation plan. But despite these battles, many people who have worked with her regard Johns as a noncombative, articulate advocate for her constituents who has had a "calming effect" on the board.

Yet Johns has also had her disputes with other members.

"She and I had a basic disagreement," said County Councilwoman Sue V. Mills, who served one year on the school board with Johns. "She believes busing is a tool to integration. I don't believe it's the proper tool.

"She's always a lady," Mills added of her former colleague. "She wears velvet boxing gloves. She can cut you right to the quick, but she does it in such a way you think, 'Is she or isn't she?' as you die bleeding of stab wounds."

Early in her tenure, Johns said, polarization among board members was much more intense than it is now. "We can talk about things now that we couldn't talk about seven years ago. I'd come home and couldn't sleep until 2 or 3 in the morning," she said.

Most recently, Johns adamantly opposed a proposal to close 22 schools, a plan that was issued last spring by the board to meet a court desegregation order.

"I felt as chairman I had to report out the action as I was directed. But as a member of the board representing one district, I had every right in the world to say how it affected my district. That did not faze me one bit," she said.

Lynn Edwards, a vice president of the county NAACP, said Johns "was always one of the stronger supporters of hearing the community's objections and concerns." Despite Johns' resignation, the number of blacks on the board will not change because both candidates for her seat are black.

Johns, who works full time as director of community service at Prince George's Hospital and Medical Center, began her career as a teacher in Louisiana. Since coming to Prince George's County in 1961, she has worked in social services, including the war against poverty in the 1960s and later as a mental health educational consultant.

County Councilwoman JoAnn T. Bell, who served on the school board with Johns from 1977 to 1982, said that Johns helped refocus the board, which had for years concentrated on busing to the exclusion of other issues.

"You couldn't have a discussion on educational programs, whether it was instruction or pencils, without first talking about the bus ride," Bell said. "Bonnie was an integral part . . . of focusing on what happened at the end of that bus ride."

Since she was chosen to head the school board last winter, Johns has been criticized for what some see as the board's mistakes.

"At the moment, teachers aren't feeling the greatest about the board, and maybe the chairman, because she stood in front of the board," said Paul Pinsky, president of the Prince George's County Educators Association. "We had a difficult year," he said, referring to a drawn-out contract negotiation last spring and the lack of a contract when schools opened last year.

But Pinsky also characterized Johns as "a very good role model" who visited schools frequently and "spoke for her constituents."

Although some of her constituents have urged her to remain in politics, Johns says she sees no future there. "I have no craving. I have no motivation," she said.

She has, however, entered a new arena, heading a committee urging the modification of TRIM, the county's property tax cap.

That move follows what Johns calls "a very ugly experience" last year when she ran for the Maryland Senate seat vacated by Tommie Broadwater, who was convicted of food stamp fraud. The 22-member county Democratic Central Committee voted to give the post to Orphans Court Judge Decatur Trotter.

"The old-boy network took control," Johns said, and afterward she was even more disenchanted with politics.

During Johns' "difficult years" on the school board, she and other officials have been forced to confront sharply declining enrollment and the closing of 65 schools. Johns has long contended that more schools have been closed in the heavily black inner-Beltway neighborhoods than elsewhere and that more black children than white have been bused out of their communities.

A year ago, Johns was one of two members to vote against appealing the federal court decision that the county schools were never fully desegregated after a 1972 court order. She said she was "unwilling to spend another dime" on the appeal, which is to be heard sometime this fall.

Finally, she believes the board's most recent proposal to close 22 schools -- the measure is in limbo while an expert panel studies the case -- is another example of discrimination against the heavily black areas of the county.

"It looks like we're still being bused in many ways we shouldn't be bused," she said. "Black people feel their communities are still being dispersed heavily.

"You can go through the statistics and go through the busing motions; the statistics and the percentages may be right. But unless things are right inside of that classroom, all can be lost.