The vast majority of states don’t give their schools much of an incentive to bolster achievement for the most advanced students, according to a report released Wednesday by the Thomas B. Fordham Institute, a think tank in Washington.

In fact, just four states have accountability systems that the think tank deemed “praiseworthy” when it comes to focusing on these students. Those states include: Arkansas, Ohio, Oregon, and South Carolina.

Part of the problem: Only a small handful of states—Arkansas, Colorado, Idaho and Oregon—base half of a school’s rating on improving performance for all students. And seven states plus the District of Columbia don’t consider growth at all.

“Given that student growth is the best way to evaluate schools’ impact on student achievement--and the best way to signal that all kids matter--this finding is extremely alarming,” according to the Institute’s report.

What’s more, just five states break out gifted kids as a separate “subgroup” and measure their performance separately, including Nevada, North Carolina, Ohio, Oregon, and Wyoming.

Here’s how the Fordham Institute thinks states stack up. Fordham considered both states that give schools an overall “summative” rating. (Check out page 13 of the report for a detailed explanation of its methodology.)

The Institute doesn’t think the department’s proposed ESSA regulations do enough to encourage states to measure student achievement using a performance index, and could even disallow it. The Fordham Institute and more than a dozen researchers want that tweaked in the final regulations, expected later this year. (More here.)