WASHINGTON — A congressional proposal to make No Child Left Behind more flexible would riddle the five-year-old education law with loopholes, Education Secretary Margaret Spellings said yesterday.

"We must refuse to make any changes that would make us less accountable for educating every child to grade-level standards in reading and math," she said in a speech to business leaders.

The 2002 law, which is now up for renewal, requires annual testing in grades three through eight in math and reading. Schools that miss yearly goals face consequences, such as having to pay for tutoring or replacing principals.

The House proposal, being circulated by senior Democrats and Republicans on the education committee, would allow schools to get credit for tests in subjects other than math and reading.

Committee Chairman George Miller, a Democrat from California, said that would give educators a fuller picture of how students are doing.

Spellings said that would water down the law. She sent Miller a letter yesterday outlining her concerns.

A provision that would allow children with limited English skills to take tests in their native language for five years — up from three — is also running into opposition from the Bush administration.

And another point of concern, Spellings said, is a plan that could increase the number of special education students taking tests that are easier than the regular exams.

Miller countered that parents and educators have been clamoring for such changes to the law since it was passed five years ago.

"We've learned a lot in those five years, and this is an attempt to be smarter, fairer and better at what we're doing," Miller said.

The congressional proposal also distinguishes between schools that fail to meet annual goals by a little from those that fail by a lot. Spellings said she generally likes that but said the House bill would reduce the likelihood struggling students in the lower priority schools would get tutoring — something she opposes.

The administration and congressional lawmakers agree on one key change. They want schools to measure the performance of individual students over time rather than comparing the scores of students in a certain grade to students in that grade the year before.