Just over 70 percent of Prince William County's 3,047 sixth-graders passed the newly mandated state literacy test, a rate that ranked the county fifth among other Northern Virginia jurisdictions.

Children who failed any or all portions of the examination of reading, writing and math, will have two more chances to pass the entire test before ninth grade.

School officials last week also released scores for standardized tests given to about 15,140 county students last spring. Children in first, second, fourth, eighth and 11th grades did slightly better than last year -- encouraging results, school officials said.

"The trend is upward, and I think that's a positive sign," School Superintendent Edward L. Kelly said last week. "One of the most heartening things is the number of kids {scoring} in the bottom {25 percent of the test} has dropped . . . . But we don't think standardized tests are the only test of whether children are getting a good education."

Test results, which many politicians and members of the public regard as a gauge of school quality, showed Prince William holding its middle position among Northern Virginia school divisions.

The county's pass rate for the "literacy passport" followed Loudoun, Arlington and Fairfax counties as well as the city of Falls Church. Prince William children did best in reading, where the pass rate was 87.2 percent, and worst in writing, where the rate was 79.6 percent. In math, students passed at a rate of 85.4 percent.

The test, to be given each spring, is based on the state-mandated core curriculum for sixth-graders. Thereading portion of the exam tests comprehension. In the math section, students must compute numbers, demonstrate understanding of weights and measures, figure the perimeter of a geometric figure, and tell time, among other tasks. This past year's writing sample was on the topic "Something you wish you had."

Beginning in September 1992, those who have not passed all three parts of the test cannot enter ninth grade.

In the standardized test results, students did best in science, where the average scores for fourth-, eighth-, and 11th-graders hovered in the 70th percentile.

County school officials now have three years of data for comparison of students' performance on the Riverside basic skills tests, which were adopted by Virginia for statewide testing beginning with the 1987-88 school year. The tests, which examine students in a wide array of subjects from language arts and math to science and social studies, is a "nationally normed" test, which uses a national sampling of scores as a benchmark for local scores.

For example, if a local child scores in the 90th percentile, the score is among the top 10 percent of those in the national sample. By the same token, a score in the 25th percentile constitutes performance in the lowest quarter of those in the sample.

School officials took heart from gradual improvements in scores and the fact that 44 percent of the county's children score in the top quarter nationally.

Kelly, however, acknowledged the wide gap between the performance among black and white students, which appears to widen between grades four and eleven. While the gap between standardized test scores for blacks and whites in fourth grade is between 14 and 20 points on different portions of the test, by 11th grade the span is between 20 and 29 points.

One of the goals set by the school board is to narrow the gap in performance between black and white students. Approximately 18 percent of the county's 42,000 students are black, and the proportion has been rising steadily in recent years.

Kelly has refused to tell schools how to improve test scores, preferring instead that principals and teachers develop plans for their own schools under school-based management, which will start in all 58 schools this fall.

"Area superintendents will be analyzing scores by building and working with principals for improvement," Kelly said. Attention will focus not only on schools where scores dropped, but also on those "where there's no increase."

"Is it due to curriculum, instruction, or a combination of both?" Kelly said.

Under state law, children who don't pass portions of the literacy passport or who score at the 25th percentile or below on standardized tests, must be given the option of attending tuition-free summer school and receiving extra assistance during the next academic year.

PERCENTAGE OF SIXTH-GRADERS WHO PASSED LITERACY PASSPORT TEST

SCHOOL..................READING...WRITING.....MATHEMATICS

Brentsville Middle.........87.2.....69.1.....77.6

Godwin Middle..............85.4.....80.4.....79.9

Graham Park Middle.........82.9.....72.4.....80.7

Lake Ridge Middle..........95.7.....92.8.....93.1

Lynn Middle................85.6.....74.6.....87.6

Marsteller Middle..........86.0.....85.0.....86.1

Parkside Middle............88.8.....77.4.....82.3

Rippon Middle..............80.6.....60.8.....73.3

Saunders Middle............92.8.....85.2.....90.4

Stonewall Middle...........81.6.....82.4.....91.0

Woodbridge Middle..........86.7.....80.9.....85.9

PERCENTAGE OF SIXTH-GRADERS WHO PASSED

PASSIGN RATES FOR ALL THREE TESTS

ALEXANDRIA..................52.2%

ARLINGTON................... 73.8

FAIRFAX CITY................ 80.8

FALLS CHURCH................ 79.1

LOUNDOUN COUNTY............. 72.4

PRINCE WILLIAM COUNTY....... 70.1

MANASSAS.................... 67.8

MANASSAS PARK............... 34.1

STATEWIDE................... 65.1

PASSING RATES FOR SEPARATE TESTS

JURISDICTION............READING.......WRITING.....MATHEMATICS

Alexandria..............72.1%..........67.7%.......73.4%

Arlington.............. 86.9.......... 80.2.........88.5

Fairfax County..........89.8...........88.9.........90.7

Fall Church.............94.6...........85.3.........93.5

Loundoun County.........86.2...........88.3.........86.8

Prince William County...87.2...........79.6.........85.4

Manassas................83.5...........80.3.........86.1

Manassas Park...........59.8...........56.5.........58.7

Statewide...............82.3...........77.0.........81.5

SOURCE: State Board of Education