As policymakers over the past decade focused on closing the achievement gap between white students and underrepresented minorities, another rift was widening: the one between Asian American students and everyone else.

A new study from the Center on Education Policy underscores how significantly Asian American students outpace their peers.

The data focus on student achievement on eighth-grade state standardized tests, including a rare analysis of student performance at advanced levels.

It is at those levels that the exceptional — and rapidly improving — achievement of Asian American middle schoolers was most pronounced.

Nationwide, the percentage of Asian American students scoring in the upper echelons on math exams was 17 points higher than the percentage of white students. Notably, that gap has continued to widen in recent years.

“The lesson for other groups is that effort counts. Asian American students are working harder, doing better and getting ahead,” said Jack Jennings, president of the Center on Education Policy.

Jennings points out that the Asian American subgroup is an imperfect monolith, including students whose families hail from countries as diverse as Japan and Jordan.

There are clear disparities within the subgroup. Pacific Islanders, for example, don’t perform as well as Korean students on standardized tests.

But in most states, Asian Americans — sometimes labeled a “model minority” — outperformed all other subpopulations. Some scholars are quick to argue against that label, saying it plays down the diversity, and the challenges, that pervade the subpopulation.