DC’s Test Scores: Raise a Toast with Glass Half-Full
Mayor Vincent Gray, DCPS Chancellor Kaya Henderson, and school officials across DC are understandably proud of the 2013 DC Comprehensive Assessment System (DC-CAS) scores. Scores on these standardized tests are the highest they have ever been since the city began administering the DC-CAS in 2006. For the first time, more than half of public school students performed at grade-level proficiency. The overall percentage of students demonstrating grade-level proficiency increased four percentage points since 2012, representing the largest single-year improvement in reading since 2008 and in math since 2009. All sub-groups and all grades experienced at least some growth. This is fantastic news. So why am I cautiously optimistic?
First, we simply don’t have all the information yet. The Office of the State Superintendent of Education has released a summary of DC-CAS scores, along with PDFs of school proficiency rates in math and reading compared to 2012 scores. More detail on sub-group performance in each school must be an important part of the discussion, as well as further analyses to make sure all the improvements we’re touting are statistically significant, and to control for changes in the composition of our student population since 2006.
It also would be worthwhile to probe beyond proficiency rates, which are only one way to interpret DC-CAS scores. The DC-CAS has four score levels: Below Basic, Basic, Proficient and Advanced. Proficiency rates tell us what percentage of students scored Proficient or Advanced in a given year. But there are other measures that could give us a different or more nuanced picture of school performance. In DC Action’s brief on third grade performance, we created a weighted score that took into account the number of students in each score bracket, not just “above” or “below” proficient. Christina Henderson, Legislative Director for Councilmember David Grosso, highlights Median Percentile Growth (MPG), a measure of how much the students in a school improve each year, regardless of where they started.
Don’t get me wrong; the summary report is encouraging – as far as it goes. I especially applaud those schools that saw double-digit improvements in proficiency this year. What an amazing accomplishment! However, if we want to see these successes continue, we need to better understand where and why improvements are (or aren’t) occurring. DC Action will be diving deeper into DC-CAS data as it becomes available, in order to answer some of these questions. Before we pop any champagne, let us also remember that half of DC’s students still aren’t performing at grade level, and these students are disproportionately affected by challenges such as poverty, language barriers, or a disability. I think everybody – even those celebrating the loudest today – knows we still have a long way to go before every student in DC is achieving his or her highest potential.