During much of the last decade, schools that were found lacking under the federal No Child Left Behind law were labeled as “failing.” Year after year, the list of schools not making adequate yearly progress grew. By 2010, about half of Minnesota’s 2,000 schools were on that list. The designations were based largely on reading, math and writing test scores.

But in 2011, Minnesota received a waiver from No Child Left Behind requirements so that state education officials could develop their own Multiple Measures Ratings (MMR) evaluation system.

Last year, under the new assessment system, 214 schools were labeled underperforming in some way. This week, the Minnesota Department of Education reported that 27 schools earned their way off a section of that list because they have shown significant improvement under the new rating system.

So has there really been significant improvement? Or has changing the assessment criteria simply made poorly performing schools look better?

It’s a fair question that should be answered in the next few annual cycles of assessments. Education Commissioner Brenda Cassellius says that many of the 27 schools have been “transformed’’ and are catching up faster because of the support they’ve now received from the state.

The state report says that 78 percent of one category of low performers showed improvement on the MMR and that 33 percent of them boosted their MMR percentages by 20 or more points.

That sounds promising. If all of the lowest-scoring schools can improve at that rate in the next few years, significant progress can be made toward narrowing the state’s educational achievement gap.

The MMR rating uses four criteria (multiple measures) to assign each school up to 100 points based on proficiency, academic growth, achievement gap reduction and graduation rates.

Schools that perform in the bottom quarter of schools within their category (high school, middle school, elementary) are given one of three designations — “priority,” “focus” or “continuous improvement.” And those schools are eligible to receive additional resources to help change their instructional methods to improve student learning.

Even those skeptical of the new system agree that there were problems with No Child Left Behind designations. Even schools that were doing well for 80 to 90 percent of kids received the “failing” label because a handful of students in one or more small subsets failed a single test or were absent on test day. That certainly wasn’t a fair way to judge a school’s overall success.

Still, skeptics rightly raise concerns about the timing of the new assessments and how useful they can be to classroom teachers. They argue that they could use the information earlier in the year to address student needs. Critics also worry that the new system doesn’t put enough pressure on schools to improve. It remains to be seen what the consequences will be if schools receive state intervention and still fail to improve academic achievement.

And while the MMR report mentions the importance of schools sharing successful strategies, there should be more specifics about doing it. Good beat-the-odds traditional and charter public schools are doing well with low-income kids every day. More should be done to learn from and replicate their success.

Focusing resources on the schools and students that need them most and setting targets for them to reach is a sensible goal of the new assessments. Over time, if the targeted support to struggling schools continues to get positive year-over-year results, significant progress will be made toward narrowing and closing Minnesota’s achievement gaps.