Tennessee’s self-proclaimed status as having the “fastest-improving” students in the country is in jeopardy after the state posted flat scores on a national reading and math test.

The stagnant scores on the National Assessment of Education Performance, known as NAEP, come two years after Tennessee drew national attention for making outsized gains. But they also came as many states posted slight decreases on the exam, suggesting that Tennessee students had avoided pitfalls that other students had experienced.

Overall, Tennessee students are now on par with students across the nation in most areas of the assessment, known informally as “the nation’s report card” because it long has been the only way to compare students’ performance across states.

The results come five years after Tennessee legislators changed education policies to make the state eligible for federal Race to the Top funds. Gov. Bill Haslam cited those changes — which included adopting the shared Common Core standards and factoring student test scores into teacher evaluations — as reasons for the 2013 gains, and he said they are continuing to pay off today.

“A new set of fourth- and eighth-grade students proved that the gains we made in 2013 were real,” Haslam said. “Tennessee is distinguishing itself as the state to watch in education, and today’s announcement is a testament to all of the hard work put in day to day by our educators and students.”

How have Tennessee’s math scores changed?

During a call with reporters on Tuesday, Haslam and Education Commissioner Candice McQueen bristled at the characterization of this year’s scores as flat and argued that the new scores show that Tennessee’s academic ascendancy continues.

But Tennessee’s slight gains since 2013 were not statistically significant, and state officials later said it was not appropriate to describe the state as having higher scores.

Still, McQueen emphasized that Tennessee is on track to meet her goal of being in the top half of states in all four subjects by 2019. “Years ago, I’m not sure people would have thought that was possible,” she said.

U.S. students have taken the NAEP exams every two years since the early 1990s, in an effort to provide a consistent measure of student performance at a time when states’ standards varied widely.

Now, many states, including Tennessee, are in the process of adopting new tests that reflect shared standards, potentially allowing for more detailed and frequent comparisons of students across the nation. That means the test serves the dual role of comparing student performance across states and assessing whether states have achieved their goal of crafting more “accurate” measures of student achievement with their new exams.

Indeed, the gap between Tennessee students’ scores on the state’s own tests and their scores on NAEP was one factor that propelled state officials to adopt the Common Core standards and begin developing tests to measure whether students have met them. In recent years, the state removed questions from its existing tests that do not reflect the Common Core standards, but a test designed with the Common Core in mind won’t launch until 2016.

State officials have warned that scores are likely to fall sharply then, in line with what has happened in other states that have administered Common Core-aligned exams. The gap between Tennessee students’ NAEP and state test scores ranged from 10 percentage points in fourth-grade math to 25 points in eighth-grade math. Fifty-four percent of Tennessee eighth-graders met the state’s math proficiency bar, but just 29 percent achieved proficiency on the NAEP exam.

How have Tennessee’s reading scores changed?

Data source: NAEP Graphics by: Sarah Glen/Chalkbeat

McQueen said the NAEP results point to areas where more work needs to be done, especially in fourth-grade reading, where just a third of Tennessee students passed NAEP’s proficiency bar. Only six states had lower scores.

Declining literacy scores were a dark spot on Tennessee’s otherwise sunny state test score report earlier this year, and McQueen has made reading the center of her new strategic plan for the state’s schools. McQueen said she expects that the plan — which includes a focus on early education and overhaul of teacher preparation programs — would help catapult Tennessee students’ reading scores on both the NAEP and state tests in the future.

“These scores shine a light on places we know we can improve,” she said. “We have to have renewed focus on all students’ reading abilities.”