A Fairfax County school board's compromise pay increase of 6 percent last week brought little joy to teachers who were hoping for more. But the Fairfax teachers fared better than those in Arlington where educators' pleas for a 7 percent raise in salaries were thwarted by a potential threat from the County Board.

More than 1,200 Fairfax teachers showed up at the school board meeting to protest what they expected would be a 5.5 percent pay increase - trimmed from their original request of 7.1 percent - after the County Board of Supervisors cut $5.4 million from the school budget. Instead, the school board ordered School Superintendent S. John Davis to make across-the-board cuts in the budget totaling $899,000 to fund the extra half of 1 percent increase to 6 percent.

In Arlington on the same night, however, the school board agreed to increase teachers' pay by only 5 percent, the same percentage that the County Board had promised to other county employes.

Last month, the Arlington County Board approved a school budget of $46.5 million, $1.28 million less than the school board had requested. School Superintendent Larry Cuban told the school board that more than $700,000 could be saved if teachers pay increases were trimmed from 7 to 5 percent. Cuban said that failure to cut the salary increases would mean "probable retaliation" from the County Board, which still controls a $1.2 million contingency fund for the schools. Such retaliation would cause a "drastic retrenchment" in school programs and employes, Cuban said.

"The County Board's intention is to have all employes, school and county, receive 5 percent," Cuban said. "That is both clear and firm." The County Board's control of the contingency fund was "clearly calculated to squeeze the school board," he said.

All of the Arlington school board members, who had supported a 7 percent increase for school employes, reluctantly agreed to the cut.

"When it comes to the point of playing confrontation politics . . . I can't see playing at the expense of the students," board member Ann Broder said.

Arlington teachers at the meeting had asked the school board to stand up to the County Board and grant the full 7 percent increase, especially because teachers received only a 2 percent increase last year. Marjorie Sale, representing the Arlington Education Association, called the budget threat "blackmail" and said the teachers have requested an investigation of the legality of the contingency fund by the Virginia Attorney General's office. She suggested cutting the alternative traditional school scheduled to open next year from the budget because it has a "constituency" and the loss would be noticed by the community.

"If this means finding money and reducing services to the community - so be it," she said. "This is a wealthy community."

In Fairfax, teachers had argued that the school board was obligated to honor a commitment to increase salaries by 7.1 percent, a figure the school board agreed to in formal negotiations two years ago before a State Supreme Court declared collective bargaining unconstitutional. The court decision has made the agreements no longer binding.

The Fairfax school board's approval of the 6 percent pay increase, reached after an hour and a half of debate, automatically raised the school's blue collar employes salaries to slightly more than their counterparts on the county side. Some school board members, particularly Robert Smith of Annandale District, said they felt that the imbalance was justified because county blue collar employes have been earning 1 percent more than school employes for the past year.