Some metro Atlanta school systems posted surprisingly large declines on the latest SAT, even as the state's ranking on the popular college entrance exam held steady at No. 46.

Several metro counties saw average SAT scores plummet by double digits, including 17 points in Gwinnett County, 19 points in DeKalb and 35 points in Henry, according to data released Tuesday by the state Department of Education.

Of the 11 metro school systems with more than one high school, nine saw declines in their average scores this year. Just two — Forsyth and Fulton counties — demonstrated gains.

Linda Mitchell, who oversees testing for Gwinnett's public schools, said the district is trying to determine why scores dropped. "We just don't know what happened and when you look at how we did on other tests, it doesn't make much sense," she said.

A year after Gov. Sonny Perdue crowed about Georgia's climb from the bottom of the SAT barrel, the state's overall scores fell five points to 1472.

The good news for Georgia's ranking? Everybody else in the nation did worse, too. Nationally, average math, reading and writing SAT scores fell seven points to 1511, according to the College Board.

"While we never like to gain ground by allowing our scores to go down, Georgia was again able to close the gap with the national average, continuing a positive trend for the sixth year in a row," the governor said in a statement.

Math scores for Georgia's 2007 high school class fell one point from last year to 495 out of a possible 800, and reading scores stayed the same at 494. Scores on the writing portion of the test, added in 2006, tumbled four points over the previous year to 483.

This was the second year students took the longer, redesigned version of the widely used college entrance exam. The new SAT has a top score of 2400 instead of 1600 and includes higher-level math problems and an essay portion.

While many area systems have struggled on the new test, others have excelled. Fulton officials attributed their improvement to years of providing on-campus SAT prep classes and preliminary-SAT exams for both sophomores and juniors.

"At the risk of sounding immodest, I'm not surprised," said Peter Zervakos, the principal of Northview High School, which was the top-scoring campus in the metro area.

"In Fulton County, we realize that this is very valuable to our students. The kids have got to perform well on the SAT and ACT, and all of our high schools put a great emphasis on preparing the kids."

Last year's scores on the debut test marked the sharpest drop in 31 years, a decline the College Board attributed to some students taking the test once instead of twice. Students generally fare better on the second try. But this second year of declining figures has critics talking.

"The test is exhausting and fundamentally flawed," said Bob Schaeffer, public education director for Fair-

Test, a Massachusetts-based group that often opposes standardized testing.

"It's not the common yardstick the College Board promised."

Officials of the College Board, the nonprofit organization that owns the exam, said the national declines were not statistically significant and attributed the drops to a larger and more diverse pool of test-takers. In Georgia, about 69 percent of all graduating high school seniors took the exam.

Georgia long ranked among the top states in SAT participation, but the rival ACT is gaining popularity. Since 2003, ACT participation in Georgia has jumped by more than 56 percent.

Christine Parker, a consultant with the Princeton Review, a test-prep company, said more students are taking both the SAT and the ACT — trying to hedge their bets when it comes to college admission.

"We definitely did see more students, who, instead of taking the SAT twice, are taking the ACT," she said.

Sue-Anne Liverpool, who graduated from South Gwinnett High School in May, said she took both the SAT and ACT.

But Liverpool, 18, said she didn't do substantially better on one exam vs. the other.

"But ... I got into college," she said, "so I'm fine with it."

— Staff writers Laura Diamond, Diane Stepp and Kristina Torres contributed to this article.