The Arlington School Board gave tentative approval last night to a 6.5 percent across-the-board raise for teachers and other school employes.

The raise, expected to get final approval along with the entire school budget proposal Thursday night, is a compromise between the Arlington Education Association, the local teacher group, and Superintendent Larry Cuban.

At a budget work session last week, angry teachers spoke in support of a 7.5 percent salary increase. They criticized Cuban's proposal, which would have given school employes with less than 15 years of experience an average 7 percent raise but would have given those with more years on the job 3.4 percent raises plus a special, one-time payment of $625.

George Long, a member of the Education Association, called Cubanhs proposal "a one-time bribe to drive a wedge between our faculty."

The 6.5 percent increase was strongly supported by the County Council of PTAs, according to board member Dr. Thomas L. Penn.

The decision will add approximately $293,000 to a school budget that it already exceeds by $590,000 the $38,1 million spending ceiling suggested by the Arlington County Board. Several school board members pointed out, however, that the County Board is recommending a 6.5 percent raise for county employes.

"What is right for their own people should be right for ours," declared School Board Chairman Mary Margaret Whipple.

Teacher salaries represent 83 percent of the school board budget. Last year the school board requested a 7 percent raise, but the County Board reduced it to 5 percent.

"They're going to argue on the budget as a whole with us, but not on employe salaries" this year, Penn said. "We're firm on that."