Reading and math scores on citywide tests fell this year in several D.C. schools that came under scrutiny for potential security breaches in the previous year’s exams, according to data made public Tuesday.

In a few cases, the plunge recorded through the D.C. Comprehensive Assessment System was especially stark.

At Noyes Education Campus in Northeast Washington, the pass rate in reading dropped more than 25 percentage points, to 32 percent, and the pass rate in math dropped more than 20 points, to 28 percent.

Noyes was one of three schools for which some 2010 scores were invalidated in May after an investigation found evidence or strong suspicion of cheating.

The two others were Leckie Elementary in Southwest and C.W. Harris Elementary in Southeast. At Leckie, pass rates slid slightly this year in both subjects. At C.W. Harris, there was a two-point uptick in the reading pass rate, to 21 percent, and an eight-point drop in math, to 8 percent.

Test scores can rise and fall from year to year for various reasons, including teacher and student turnover. What is unclear is whether heightened test security this year played a role in changing results at those three schools or others where student answer sheets from years past have shown unusually high rates of erasures. Experts track erasure rates to flag classrooms and schools where cheating may have occurred, with adults switching or helping to switch answers from wrong to right.

Questions about test security have arisen this year in Atlanta, Washington, Baltimore and elsewhere. D.C. Schools Chancellor Kaya Henderson, who has repeatedly expressed confidence in the city’s testing program, was not available Tuesday to comment.

Tamara Reavis, director of assessment and accountability for the office of the state superintendent of education, said D.C. officials are still analyzing the results. But she added that test security was strengthened this year. “We do feel the security for 2011 was superior,” she said, “and we stand by the validity of these results.”

Last month, D.C. officials released citywide summaries of test results that showed mostly flat achievement trends compared with 2010 in much of the school system, while scores for independent public charter schools showed modest gains. Tuesday’s release from the state superintendent’s office provided a detailed look at scores for each school.

Results are used to rate schools and are a factor in teacher evaluations.

A Washington Post review of data on 11 schools in which some classrooms were flagged for high erasure rates on 2010 tests found that scores declined this year in several. There were double-digit drops in pass rates for reading and math at J.O. Wilson Elementary and LaSalle-Backus Education Campus, both in Northeast Washington, and at Whittier Education Campus in Northwest.

But the trend was not uniform. Among the 11 schools, pass rates in math rose nine points at Plummer Elementary in Southeast, to 36 percent, and five points at Truesdell Education Campus in Northwest, to 42 percent.

Staff writer Bill Turque contributed to this report.