Eighth-grade students across the United States showed some improvement in math and science over the past four years, but fourth-graders’ performance was stagnant and students in both groups continued to trail many of their peers in Asia, according to the results of a major international exam released Tuesday.

The Trends in International Mathematics and Science Study was administered to nearly 600,000 students in dozens of education systems across the globe in 2015. US scores are likely to stoke renewed debate among politicians, educators, and business leaders about why math and science achievement has not improved more quickly relative to other nations.

US fourth-graders, for example, scored an average of 539 out of 1,000 possible points in math, down two points from the average in 2011.

Scores have risen at both grade levels and in both math and science since the test was first given in 1995. Matt Larson, president of the National Council of Teachers of Mathematics, said the trend is heartening.

‘‘We have much more work to do and achievement is not as high as we would like to have it,’’ Larson said. ‘‘But the trajectory is positive, and it may indicate that some of the efforts we’ve made over the past two and a half decades are making a difference.’’

The average math score of US fourth-graders put them behind students in 10 systems: Singapore, Hong Kong, South Korea, Taiwan, Japan, Russia, Northern Ireland and Ireland, Norway, and the Flemish portion of Belgium.

Washington Post