The percentage of Montgomery County students who passed standardized reading and math tests increased among nearly all ethnic groups and grades, with fourth-graders reaching record-breaking proficiency levels, according to a school system analysis of data provided by the Maryland State Department of Education this week.

On average, 82 percent of the county's elementary school children scored at or above proficiency levels on the reading and math Maryland School Assessment (MSA) this year, school officials said.

Among all ethnic groups, African Americans and Hispanics posted the highest gains in all grade levels. For example, 75.9 percent of Hispanics in the fourth grade passed the reading test, a 10.7 percent increase from last year. The percentage of African American fourth-graders passing the reading test increased by 7.8 percent to 76.4 percent.

"These results confirm what we said five years ago, that if we set high expectations for our children and gave them the skills to succeed, they would set academic records for years to come," Montgomery Schools Superintendent Jerry D. Weast said through a spokesman. "This is just the beginning."

Students who took the battery of tests in March were divided into three categories: advanced, proficient and basic. Students must score at the advanced or proficient level to pass.

Statewide, elementary and middle school students posted notable gains in reading and math, with black and Hispanic students slightly narrowing the gap between them and their white and Asian classmates, according to state data.

The scores will help determine whether schools and school systems meet benchmarks required under the federal No Child Left Behind law. If they do, they are deemed to have reached "adequate yearly progress." Those results are expected to be released next week.

Schools can face a variety of sanctions if scores don't improve enough for students in all ethnic groups tested -- African American, Asian American, Hispanic, and white -- as well as those receiving free and reduced-price meals, special education services and English language instruction. All students must be proficient in reading and math by 2014.

Montgomery officials said they were most pleased with the performance of fourth-grade students; 86.4 percent passed the reading test, while 83.5 percent were proficient in math, the highest of any grade's overall performance since the district began administering the MSA. The figures are up 4.5 percent and 3.5 percent, respectively.

Faith Connolly, acting director of shared accountability for the school system, said the fourth-graders were part of the first class of students to benefit from the early-childhood educational reforms that were started five years ago. Those reforms include full-day kindergarten, better training for teachers, a revised curriculum and regular testing of students to see how they are progressing. Reading scores for those students have improved over the years, even as the students have grown more diverse, school officials said.

"That was very rewarding for us to see, that that group is not just maintaining but sustaining and growing," Connolly said. "That's very satisfying."

But not all Montgomery students posted higher scores.

Sixth-graders saw slight declines in their performance among a few groups of students. Overall, the percentage of sixth-graders passing the reading test dropped by 1.4 percent to 75.8 percent. Sixth-graders did show improvement in math, with 67.7 percent passing, up from 62.4 percent the previous year.

The percentage of black sixth-graders passing the reading test dropped to 59 percent from 61.7 percent last year, while the percentage of Hispanic sixth-graders scoring proficient in reading dropped to 55.9 percent from 56.7 percent last year. Even whites posted a slight decline. School officials said the gap between minority students and their white and Asian counterparts in grades 6, 7 and 8 did not narrow as much as it did in other grades.

The only other groups to see declines in their scores were sixth-graders living in poverty and sixth- and seventh-grade special education students. All three groups faltered on the reading test but not in math.

Frieda Lacey, deputy superintendent of schools, said the drop in scores among sixth-graders was further proof that the school system has to revamp its middle school program. A recent audit found several inconsistencies in the way teachers are trained and the way in which students are taught and disciplined in those grades.

"We haven't focused on the middle school, and that's what we're embarking on in the fall," Lacey said. "We're taking a close look at middle schools across the board."

Still, officials said they had more to celebrate than be concerned about. In particular, they highlighted the gains made by students at Viers Mill Elementary School in Silver Spring. The percentage of third-graders with limited English skills who reached the proficiency level went from 54 percent in 2004 to 90 percent in 2005.

"That is just unheard of," Lacey said. "I think they've done a phenomenal job. They have really proven that strong leadership in the building and high expectations and the reforms we have put in place really make a difference."