Test scores in math and reading dropped in DC Public Schools between 2008 and 2012, while they improved in public charter schools, according to a study released Wednesday.

Using the median school's performance to determine a "typical" school, the study by the DC Fiscal Policy Institute found that the typical DCPS school showed a decline in the number of students who rated "proficient" or "advanced" on the DC Comprehensive Assessment System exams in reading and math across elementary, middle and high schools, except for the typical middle school, where the number of students proficient or advanced in math spiked from 42.7 percent in 2008 to 61.2 percent in 2012.

By contrast, the typical public charter school saw an improvement in reading and math proficiency across all age levels, except for high school reading, which remained largely unchanged.

Making the grade
The median number of students scoring "proficient" or "advanced" on D.C. standardized tests:
By age group
Math 2008 Math 2012 Reading 2008 Reading 2012
Elementary 38.7 percent 43.8 percent 44.9 percent 38.3 percent
Middle 42.7 percent 61.2 percent 43.2 percent 47 percent
High 28.6 percent 31.6 percent 27.4 percent 31.1 percent
Education campus (elementary and middle) 43.2 percent 47.8 percent 49.4 percent 39.4 percent
All schools 39.3 percent 44.9 percent 44.9 percent 38.4 percent
By school type in 2012
Overall Reading Math
D.C. Public Schools 36.7 percent 35.4 percent 37.6 percent
Public charter schools 50.2 percent 50.5 percent 53.9 percent
All D.C. publicly funded schools 41.2 percent 38.4 percent 44.9 percent
By ward
Overall 2008 Overall 2012 Change
Ward 1 45 percent 56.1 percent 11.2 percent
Ward 2 58.6 percent 60.5 percent 1.8 percent
Ward 3 77 percent 83.3 percent 6.3 percent
Ward 4 48.6 percent 43.8 percent -4.8 percent
Ward 5 40.4 percent 38.4 percent -2 percent
Ward 6 39 percent 42.8 percent 3.8 percent
Ward 7 35.8 percent 33.1 percent -2.7 percent
Ward 8 29.2 percent 22.8 percent -6.4 percent
Source: DC Fiscal Policy Institute

Theola Labbe-DeBose, a spokeswoman for the DC Public Charter School Board, attributed charters' performance to their independence from city bureaucracy.

"What we know from our charters and from our oversight is that autonomy -- the freedom to innovate with curriculum, hiring, policies and budget -- is central to D.C. charter school results," she said. "Autonomy alone won't make a school excellent, but we believe it is a condition for excellence."

She also pointed to the board's "aggressive" approach to closing underperforming charter schools. Since 1996, one out of three charter schools opened in the District has closed, she said.

But even at the typical charter school, only half of students rated "proficient" or "advanced" in math and reading on the standardized tests last year, according to the study.

"Overall, the District has a long way to go citywide," said Soumya Bhat, the Fiscal Policy Institute's education finance and policy analyst. "Even when we're talking about the charter schools ... we're still just talking about a 6 percent increase over four years."

Across the 109 DCPS schools and 43 charters studied, overall proficiency levels slipped over the four-year period, from 41.8 percent to 41.2 percent. Most of the change is the result of reading scores dropping 6.5 percent at the typical school, according to the study. Lower grades saw the greatest drop in reading scores.

Math proficiency, on the other hand, increased 5.7 percent across all schools, to 44.9 percent.

The schools with the greatest declines in proficiency were those in Wards 4, 5, 7 and 8, the study found. In the report, Bhat said that finding was of particular concern because the schools in Wards 7 and 8 were already the lowest-scoring before the drop.

Bhat recommended giving more money to schools with more low-income students, which she said the D.C. deputy mayor for education is currently studying. Bhat also recommended putting more money toward mental health services, after-school activities and efforts to engage parents.

DCPS is still reviewing the findings, said spokeswoman Melissa Salmanowitz. She declined to comment further.