The proportion of Fairfax County high school seniors going on to further education has risen 10 percent in six years, to 88.5 percent of the class of 1987, the county School Board was told last night.

More Fairfax County students were accepted this year than last year at five competitive Virginia state schools, but more freshmen were accepted at the schools and Fairfax students accounted for a smaller percentage of the total this year, according to a report presented to the board by Assistant Superintendent Beatrice Cameron.

School Board members have complained that local students do not get a fair shake at the competitive state schools.

More than two-thirds of June's 10,319 graduating seniors -- 70.5 percent -- went on to four-year colleges, according to the report, which stemmed from a survey of seniors in May.

"It reflects the overall trend we've seen of students becoming more serious," Cameron said in an interview.

Two-year colleges enrolled 11.2 percent of the class of 1987. Business, nursing, trade and technical schools or apprenticeship programs drew 6.8 percent.

The rest of the seniors indicated they were undecided or did not plan to continue formal education.

Most of the increase in students going on to further education was attributed to a rise in the percentage attending four-year colleges. As has been true for at least six years, more women than men planned further education. Asians were most likely to plan additional education, followed by whites, Hispanics and blacks.

Just less than 60 percent of Fairfax County graduates planned to attend schools in Virginia, reflecting a steady decrease from 67 percent in 1982.

On the controversial question of admission to the competitive Virginia state schools, the report said 21 percent of students accepted for this year's freshman class at five of those schools are from Fairfax County, compared with 23 percent last year.

But total acceptances from Fairfax County rose by 2.7 percent, to 5,250, at the five schools combined -- the University of Virginia, James Madison University, the College of William and Mary, Virginia Tech and George Mason University.

Cameron described the trend as "mixed." School Board Chairman Mary E. Collier said she was disappointed that the five schools continued to accept such a large share of out-of-state students, rather than giving preference to Virginia residents.