Scores on state reading and mathematics tests rose nearly across the board this year at Gladys N. Spellman Elementary School. The percentage of students reaching proficiency increased by double digits in grades 3 through 6, except for a dip in fourth-grade reading.

Sixty-seven percent of fifth-graders scored proficient or better on the reading test, for example, up from 51 percent in 2004 and 37 percent in 2003.

But the test results describe only part of what the Cheverly school accomplished. Enrollment data show a deeper picture.

At the beginning of the 2004-05 school year, Spellman's enrollment had dropped to 451 from 545 the year before. Many parents transferred their children after Spellman failed to show adequate progress on 2004 state tests as defined by the federal No Child Left Behind law.

Such mass transfers, although potentially beneficial to individual students, can depress scores at the school they leave if the exodus includes high achievers.

What's more, a significant number of students were coming and going every month. Thirteen left in October, six in November, eight in December, eight in January, 11 in February, six in March and three in April, according to a May 11 report.

There were six arrivals in October, nine in November, five in December, 10 in January, two in February, seven in March and six in April.

This phenomenon, known in education circles as "student mobility," ripples through schools in many ways. It forces teachers and administrators to take extra care to help new arrivals adjust. Precious time can be lost as educators track down records and assess where students are in their coursework. Students can be nervous and disoriented.

Prince George's, home to a large number of military families and many rental communities, has one of the most mobile student populations in the Washington area. Spellman was cited in a recent state report as a top performer among high-mobility schools.

To address the mobility challenge, Prince George's school officials say they have standardized textbooks and curriculum to help students stay on track when they move within the county. Still, Spellman Principal Ann Swann said she seeks to help students stay put during the school year. For example, she made special arrangements for Garnett Stephens Jr. to finish sixth grade at the school after his parents moved from Cheverly to Clinton in November.

"When you want maximum impact in education, it's very important that the child be stable and not go from school to school to school," Swann said, "even if the curriculum is the same. Those children that have been here from kindergarten and stay here all the way -- when you look at their records, they have done extremely well."

Garnett's mother, Donna Stephens, agreed that her son was better off staying at Spellman. "He knows everybody there," she said. "Everyone knows him. The curriculum has been great."

Maryland School Assessment scores released this month include tests taken by students who arrived in a school mid-year. But ratings of adequate yearly progress under the federal law, expected to be released next week, will only count scores from students enrolled for most of the academic year.

Broad, Steep Gains on Tests

A systemwide MSA analysis found that reading and math scores rose in grades 3 through 8 for every group of students except those with limited English skills. Scores were up for American Indians, Asian Americans, African Americans, Hispanics, non-Hispanic whites, special-education students and those who receive federal meal subsidies.

School officials reported that 92 percent of elementary schools improved in reading scores and 95 percent gained in math. Every middle school gained in math, but only half did in reading, an area of concern.

At Glassmanor Elementary School in Oxon Hill, according to the test data, the percentage of students reading at proficient or better more than doubled, to 68 percent from 30 percent. At Matthew Henson Elementary in Landover, the percentage showing proficiency or better in math shot up to 61 percent from 23 percent.

Officials also heaped praise on a high-performing school for getting better. Glenarden Woods Elementary improved in reading and math even though four out of five students already were showing grade-level proficiency or advanced ability the year before.

Arrested Official Asks for Money

Shortly before the school year ended, some Prince George's teachers were surprised to see in their mailboxes monetary aid solicitations for Pamela Y. Hoffler-Riddick. An assistant regional superintendent, Hoffler-Riddick was arrested in January on money laundering charges in connection with a drug ring based in Virginia. She has denied wrongdoing and is on administrative leave.

Jeff Vandivere, a teacher who received the solicitation at Thomas G. Pullen School in Landover, said he was outraged. He suggested donations would be better aimed at sprucing up school buildings or buying classroom reading materials or technological equipment.