The reading abilities of New York City fourth graders are improving, according to the results of a national test released Thursday, but eighth graders’ scores remain virtually unchanged.

Since 2002, the city’s fourth graders have posted steady, incremental gains on the test, the National Assessment of Educational Progress, with 12 percent more students now demonstrating at least a basic command of the skills tested.

The biggest leaps occurred among New York’s neediest students, said New York City Schools Chancellor Joel Klein in a webcast earlier today, citing a 13-point gain in the mean test score for fourth-graders eligible for free lunch, most of whom are Black and Latino. Scores for white and Asian student remained relatively constant.

Overall, the city’s mean scores still lag behind New York State’s mean scores, but the city performed better than many large urban school districts. Among the 11 large urban school districts that participated in the test in 2007 and 2009, New York City was one of four that showed fourth-grade gains. Additionally, New York City’s mean scores are catching up with the nation’s mean scores.

During his webcast, Klein acknowledged that eighth grade achievement was “the largest challenge” and attributed the gains in fourth grade achievement to his reforms. The Department of Education has implemented changes that will allow each school to opt out of one-size-fits all citywide curricula. But Klein partially credited that citywide curriculum consensus for this year’s test score gains.

“We have focused relentlessly on instruction, with a core curriculum,” Klein said. “We have focused on accountability. We have focused on rewarding success, and on consequences for non-performers.”

Klein also credited teachers in high-poverty communities for their contribution to the city’s NAEP progress. “The takeaway is that in districts that apply steady, bold reforms, we see progress,” he said. “When it’s done right, when it’s done with courage and conviction, accountability, real choice, and real competition are going to drive this forward.”

Every two years, the National Assessment of Educational Progress samples student achievement nationwide. The NAEP exam is widely considered a ‘gold standard’ of achievement testing, because it’s a national measure – as opposed to individual state tests, which vary greatly in rigor and reliability.

In addition, the NAEP is a sampling test, meaning that relatively few students sit as proxies for all the city’s children. In New York City, where up to 80,000 children make up each academic grade, fewer than 5,000 fourth- and eighth-grade students sat for the NAEP reading exam.

Because so few children take the test, New York City doesn’t prepare students for the exam in any specific way. This contrasts with the schools’ and the Department of Education’s practice of preparing students for state tests, which can determine how much funding a school gets and even whether a school stays open.

Some schools start testing for state tests as early as kindergarten – although it’s hard to teach five-year-olds to “bubble in” the test forms, according to Harlem Success Academy’s Eva Moskowitz.