While largely remaining above the national median, scores of Baltimore County pupils dropped in all but one tested area on the Comprehensive Test of Basic Skills, a multiple-choice test that has been phased out.
Second- and fourth-graders taking the test in March performed worse on reading and math than pupils who took it the previous year. The second-graders' math scores fell the most, from the 71st to the 55th percentile.
Sixth-graders scored the same on reading. But on math, their scores fell slightly to the 48th percentile, two points below the national median.
Superintendent Joe A. Hairston expressed disappointment with the results, but he cautioned against reading too much into them, especially because the CTBS test was being phased out last school year.
"Even though we have a dip here, our scores are still above the national level -- that's an indication of stability," he said.
On the reading portion of the test, second-graders' scores fell from the 68th to the 64th percentile, and fourth-graders' scores dropped from the 61st to the 56th percentile. Sixth-grade reading scores stayed at the 56th percentile.
Fourth-graders' math scores dropped from the 63rd to the 52nd percentile, and sixth-graders' math scores declined two points.
"I can't think of any legitimate reason to explain that away except for a problem with instruction," said Michael Franklin, president of the PTA Council of Baltimore County. He singled out math instruction as especially needing improvement.
CTBS is a national test of basic skills such as arithmetic and reading comprehension.
Despite the overall drop in scores, there were some bright spots in individual results. Winfield Elementary and Woodlawn Middle, two of the three county schools eligible for state takeover, saw their scores rise in all tested areas.
Sixth-graders at Southwest Academy, Sparrows Point Middle and Woodlawn Middle have had some of the highest average increases over the last four years.
"It just goes to show that school improvement is in place, and we have the right focus," said Jerilyn Roberts, Woodlawn Middle's principal, who attributed the gains to a daily emphasis on making pupils learn what they're supposed to.
This was the last administration of the CTBS, which has been replaced because of new state and federal mandates for tests measuring individual student performance.
The Maryland School Assessments, the tests supplanting the CTBS, were given for the first time in March. But like most other districts, Baltimore County schools opted to give the CTBS one last time as a diagnostic tool.
Some experts said scores can drop on the last administration of a standardized test as teachers shift their focus elsewhere, and Hairston said the end of CTBS may have played a role in the final administration's poor showing.
"The fact that this was a voluntary test that we're not going to be using anymore could have played a part in the outcomes," Hairston said.
Yet Hairston conceded the scores showed that the school system has some improving to do, especially in math instruction. He also said the school system needs to do a better job aligning what is taught with what is tested.
School officials pointed to efforts at Deep Creek Elementary in Essex as a model for pending changes.
Last school year, Principal Anissa Brown-Dennis figured a new literacy program for kindergartners and a shift to phonics instruction would help pupils' reading skills, and she ordered 90 minutes of math instruction every morning for every pupil.
In addition, Brown-Dennis asked first- and second-grade teachers to identify poorly performing pupils and give them extra help after school.
While Deep Creek fourth-graders' scores on the CTBS fell last school year, Deep Creek second-graders' math scores rose six points to the 58th percentile, and their reading scores jumped eight points to the 50th percentile.
"We're seeing that what we're doing so far is working," said Brown-Dennis, who plans to expand the after-school tutorials to more grades next school year.
Another model for changes is Perry Hall Elementary, where Principal Karen Harris has invited teachers to plan lessons together. Teachers develop the lesson plans to satisfy Maryland standards, try out the plans and then refine them.
The school's CTBS scores dropped in all tested areas, but Harris expects the "lesson study" initiative will result in gains on the MSAs.
"I'm confident that it is going to have a positive impact on student achievement," Harris said. "We're expecting more of students, and we're changing the quality of instruction so students can achieve at a higher level."