Higher D.C. public school test scores were the result of new grading system

WASHINGTON (AP) - District of Columbia public school test scores that were hailed as historic highs in July were the result of a decision to score the tests in a way that yielded higher math scores.

The Washington Post reported Sunday that the 2013 test results showed four-point gains in math, even though D.C. students got far fewer math questions correct than in 2012.

The decision on scoring was made after D.C. teachers had recommended a new grading scale that would have held students to higher standards on new, tougher tests. But officials reviewed projections that the grading scale would result in declines in math proficiency rates.

Officials instead decided after students took the tests to keep the level of difficulty constant and discard the new grading approach developed by teachers, according to documents and emails obtained by the Post. The decision resulted in the largest overall testing improvement since 2008.

Experts said the decision is generally reasonable to keep scores comparable to past years. But it differs from approaches in states that transitioned to tougher tests, including Virginia and New York. Student scores dropped in those states after the introduction of more-difficult tests and tougher scoring.

The D.C. Office of the State Superintendent of Education said it was important to continue comparing student performance to past results from year to year.

"This consistency allows parents, teachers, principals and other stakeholders to see an apples-to-apples comparison of student growth," Melissa Salmanowitz, a spokeswoman for D.C. Public Schools, wrote in an email.

The district has been transitioning from local standards to Common Core curriculum over the past two years. The standardized test was revised to reflect the changes.

Testing experts said best practices call for creating a new grading scale when the content of a test changes significantly. In that process, teachers and specialists decide what it means to be proficient in the new content.

The district began that process in 2012 but decided by June 20 to discard the new grading scales in reading and math.

Greg Cizek, a testing expert at the University of North Carolina at Chapel Hill, said applying new standards and equating test results to align with old standards are reasonable and defensible approaches.

"But from a purist perspective, I think you pick your approach first and then live with the results," Cizek said. "It's not as common to pick an approach, not like it, and then go with a different approach."