College prep test scores held fairly steady in most Washington area public school districts this year, according to figures released yesterday.

More minority students than ever took the exams, mirroring a national trend. Local school officials hailed the increased participation in the Scholastic Assessment Test but said that in some cases, such as in Fairfax and Montgomery counties, the increase in minority test-takers may have contributed to declines in those groups' average scores.

Overall, Montgomery County posted an average combined math and verbal score of 1096, the highest in the region and in county history. Fairfax nearly matched that at 1094, down one point from last year, while Prince George's combined score rose one point to 889. The District average rose three points to 813, although that remained the lowest in the area.

Officials across the region say they are working to close the "achievement gap" between higher-scoring white and Asian students and traditionally lower-scoring Latino and African American students. But they note that as the test-taking pool of students grows, so does the range of ability among them.

In Fairfax County, the number of African Americans who took the test increased 11 percent, but their average combined math and verbal score dropped by 13 points. In Montgomery, the average score for blacks rose by three points, but the average combined math and verbal score for Latinos dropped 22 points. A record-high 45 percent of Latino students in Montgomery took the exams.

Fairfax Superintendent Daniel A. Domenech noted that officials have launched several new initiatives this year to improve students' SAT scores.

"We're trying very hard to close the gap," Domenech said. "I'll be very disappointed if we don't see significant improvement next year."

In Prince George's, the news was better. Maryland's largest school system saw a one-point rise countywide and among blacks in the average combined math and verbal score and a 42-point increase among Latinos, whose score had fallen 33 points last year.

The District did not provide scores by racial or ethnic groups.

"Any time you have a district that has any increase [in scores] as well as an increasing number of children taking the exam, it's good," said Prince George's Board of Education Chairman Alvin Thornton (Suitland).

In the District, 78 percent of public and private school seniors took the exams, and in Virginia and Maryland, 65 percent of all graduating seniors took the exams -- all among the highest test-taking rates in the nation.

Nationally, a record number of minority students took the SAT this year, at the end of a decade that saw average scores rise for all racial and ethnic groups except Latinos and Mexican Americans, the College Board said. The College Board lists Latinos, Mexican Americans and Puerto Ricans in separate categories.

Minorities made up a third of the 2 million students who took the college placement exam last year, up from one-fourth of the 1 million SAT-takers in 1989. The number of Latinos taking the SAT jumped by 77 percent over the decade, and the number of Mexican Americans increased by 71 percent.

Since 1989, the average combined math and verbal score fell by 12 points to 909 for Mexican Americans and by five points to 927 for Latino students. "The primary reason for that is the phenomenal growth in the numbers of students from those groups who are taking the SAT," said Gretchen Rigol, a College Board vice president.

African American students, however, increased their average combined score by seven points, to 856, during the decade even as the number of blacks taking the test rose almost 25 percent. Puerto Rican students increased their average combined score by 28 points, to 903, even as 23 percent more took the test.

For all SAT-takers, the combined score rose by 10 points over the decade to 1016, with a gain of nine points on the math section and a single point on the verbal section. There was almost no change in last year's national score, compared with the year before. The average verbal score stayed the same at 505, and the math average dipped one point to 511.

Parents and local school officials pay close attention to the rise and fall in SAT scores as a barometer of how schools are performing, although many educators say the scores reflect mostly the income and education levels of students' parents and should not be used to gauge the quality of a high school.

In the District, the number of public school students who took the test declined from 1,521 in the 1997-98 school year to 1,418 last year -- likely a reflection of declining public school enrollment and a small but growing exodus of students to public charter schools. School officials said they expect more students to take part this year, a result of a new college access program being launched at six high schools.

In Fairfax, where a region-high 84 percent of public high school seniors took the test last year, several African American churches and community and civic organizations mounted campaigns to encourage black students to take the SATs.

"We are trying . . . to let our principals and counselors know that we want to see more minorities in these programs," Domenech said.

Montgomery officials were pleased that the number of students taking the test reached an all-time high of 79 percent but are concerned about the drop in Latino scores and the overall minority achievement gap.

"If we don't bend that trend, we don't save public education," Superintendent Jerry Weast said.

Staff writers Amy Argetsinger, Victoria Benning, Christina A. Samuels, Brigid Schulte and Debbi Wilgoren and database editor Dan Keating contributed to this report.

CAPTION: SAT Scores (This chart was not available)