Locate and recognize a detail in support of the main idea in a piece of writing. Recognize the meaning of a word as it is used in the text. Make an inference to recognize the feelings of a speaker in a poem. This is some of what fourth grade readers are expected to do on the 2011 National Assessment of Educational Progress(NAEP)—not to demonstrate proficiency—but to merely score in the “basic” range.

Fifty-six percent of DCPS fourth graders couldn’t. That’s the proportion that fell into the “below basic” category. It is two scale points higher than in 2009, the last time the test was given. Same for eighth grade math; 58 percent were “below basic” in an exam that expected them to use measuring cups to describe a fraction. Or solve a word problem that involves computing money — even with the help of a calculator. That’s a four-point improvement over 2009 and 13 points better than 2003. But it still leaves the District near the bottom of the 21 urban school systems tested. Only Cleveland, Milwaukee and Detroit had higher “below basic” populations in eighth grade math.

My colleague Lyndsey Layton has the other dispiriting details here, including the vast black-white achievement gap in DCPS that is the largest among the 21 urban systems that are part of the test.

The results align closely with the latest DC CAS results, which also showed stagnant reading scores, marginal improvements in some math results and vast divides between schools in low and high-income communities.

While DC CAS data in recent years have been tainted by evidence of possible cheating—currently under investigation by the D.C. Inspector General—there is no such cloud over NAEP, which is administered every two years by Education Department personnel, without the involvement of local school staff.

That makes NAEP one more piece of evidence that there will be no quick “turnaround” of DCPS. This will be a slow march, filled with what Chancellor Kaya Henderson has called “hard, non-sexy work” of fixing curricula and coaching up teachers to meet the needs of children who come to school every day with enormous deficits.

In a statement Wednesday, she said just about the only thing she could say: we’re working on it.

“The most recent data reinforces our decision to aggressively improve interventions, expand and develop the level of instruction in our classrooms, and, most important, aggressively implement a rigorous new curriculum that is heavily focused on reading and literacy and also aligned to the Common Core State Standards.”