Washington ? Elementary and middle schoolers posted solid gains in math and more modest improvements in reading in national test results released Tuesday.

The test scores landed in the midst of a raging debate in Congress over renewal of President Bush’s signature No Child Left Behind education law and provided ammunition for those who want to see it extended with minimal changes.

“If we hadn’t seen progress today, I think it might have been the death knell for renewing the law,” said Bruce Fuller, a professor of education and public policy at the University of California at Berkeley. “It’s definitely going to give the proponents some evidence that five years into the experiment, we’re seeing some uptick in some parts of the country.”

Bush welcomed the news, calling it proof that his policies are “producing positive results for students across the country.”

The 2002 law requires schools to test students annually in math and reading. Schools that miss benchmarks face increasingly tough consequences, such as having to replace their curriculum, teachers or principals.

The national assessments, sometimes referred to as the nation’s report card, provide the only uniform way to compare student progress in a variety of grades and subjects across the country. The tests were administered nationwide last winter.

The math scores have generally been on a steady upward trajectory since the early 1990s, well before the No Child Left Behind law was enacted.