Duncan has warned that 82 percent of U.S. schools could be labeled failures next year if No Child Left Behind isn't changed. (Photo courtesy of McClatchy-Tribune Information Services)

Frustrated by what he called a “slow motion train wreck” for U.S. schools, Education Secretary Arne Duncan said he will give schools relief from federal mandates under the No Child Left Behind law if Congress drags its feet on the law’s long-awaited overhaul.

That could mean everything from granting waivers on test score requirements to flexibility on how schools spend federal funding, though Duncan offered few details because he said the department is just beginning to work on its plan.

The Obama administration has called for an overhaul of the 9-year-old federal education law by the fall, but lawmakers have indicated that won’t be possible. Duncan told reporters June 10 that his first goal is for Congress to rewrite the law, but he wants to put other plans in place in case that doesn’t happen this year.

“This is absolutely plan B,” Duncan said. “The prospect of doing nothing is what I’m fighting against.”

Duncan has warned that 82 percent of U.S. schools could be labeled failures next year if No Child Left Behind isn’t changed. Education experts have questioned that estimate.

Still, no one thinks states will meet the law’s goal of having 100 percent of students proficient in math and reading by 2014. A school that fails to meet targets for several consecutive years faces sanctions that can include firing teachers or closing the school entirely.

And Duncan hasn’t been shy about granting waivers. In 2009, he granted more than 300, significantly higher than the number given out a year earlier by his predecessor.

Federal lawmakers—even Democrats—aren’t thrilled about Duncan’s new plan after months of closed-door, bipartisan meetings hashing out changes to the law, which is four years overdue for reauthorization.