Students take the Terra Nova standardized test at the Akili Academy in New Orleans on May 27. A growing number of critics say the U.S. education system leans too heavily on standardized testing. (Edmund D. Fountain/For The Washington Post)

The standardized test, a hallmark of the accountability movement that has defined U.S. public education since 2002, is under growing attack from critics who say students from pre-kindergarten to 12th grade are taking too many exams.

Four states have repealed or delayed graduation testing requirements in the past two years. Four others, including Texas — where the idea of using tests to hold schools accountable for educating children first began — have cut the number of required exams or reduced their consequences. Boycotts, such as when 60,000 students refused to take exams this year in New York, are on the upswing.

Former president Bill Clinton said two weeks ago that students don’t need to be tested annually, as required by federal law. “I think doing one [test] in elementary school, one in the end of middle school and one before the end of high school is quite enough if you do it right,” he said.

On Wednesday, a group representing top education officials in every state and the leaders of major urban school districts acknowledged the pushback and promised to evaluate the tests they give and to ditch those that are of poor quality or redundant.

“Testing is an important part of education, and of life,” said Michael Casserly, executive director of the Council of Great City Schools, which represents 67 urban school systems. “But it’s time that we step back and see if the tail is wagging the dog.”

The urban school leaders were joined in their effort by the Council of Chief State School Officers, which represents education commissioners in every state.

Education Secretary Arne Duncan, who said in August that testing was “sucking the oxygen out of the room” and promised to do something about it, applauded the education leaders. President Obama on Wednesday praised the efforts of the education leaders and said his administration would help school districts promote “the smarter use of tests that measure real student learning.”

Robert Schaeffer of the nonprofit National Center for Fair & Open Testing said the move was too timid.

“It’s baby steps,” he said. “We’ve had 12 years of this high-stakes testing, and the evidence on the ground is that it’s not working. And the public is getting angrier and angrier.”

Teachers have always administered tests. But exams became a federal mandate in 2002 under the No Child Left Behind Act, which required states to annually test every student in reading and math in grades 3 through 8 and once in high school. States also must give three separate science tests. The data must be reported publicly and broken down by subcategories such as race, income, English language status and disability.

The data revealed jarring differences in student achievement between poor and affluent students and among black, Hispanic and white students — variations hidden when schools did not test every child, or when they reported average school test scores.

No Child Left Behind also ushered in the practice of using test scores to evaluate schools and to punish those that failed to meet student performance goals set by the federal government. Since 2011, the Obama administration has exempted most states from the most draconian aspects of the law but, in exchange, states must use test scores in part to evaluate teachers and decide which ones to keep, reward or fire. Some critics say that has increased the pressure that comes with the testing.

That requirement has become particularly thorny this year as most states migrate to new, more challenging standardized tests aligned with the Common Core State Standards. Both major teachers unions have been pushing for a moratorium on the use of test scores for employment decisions, an idea endorsed by the Gates Foundation.

“The tide on testing is turning,” said Randi Weingarten, president of the American Federation of Teachers. “But this effort addresses the symptoms, not the root cause, of test fixation. . . . It doesn’t touch No Child Left Behind’s highly consequential testing for every child, every year.”

In addition to the federally required tests, states have layered on more assessments, with many requiring exams such as an exit test to graduate high school. Local school districts and individual schools often administer more tests.

The result is that, on average, students in large urban school districts take 113 standardized tests between pre-K and 12th grade, according to data being collected by the Council of Great City Schools.

Students in 11th grade are tested the most, with as many as 27 days, or 15 percent of the school year, in one district. Students in eighth grade spend an average of five days taking annual exams required by federal law, as well as other state and local tests.

The council has embarked on the first comprehensive analysis of the testing that exists in major urban systems and will make recommendations about ways to lighten the testing burden, Casserly said.

Two bills in the House would get rid of the federal requirement to test annually and instead instruct states to assess students once during a span of several years.

Sen. Lamar Alexander (Tenn.), a former education secretary and the ranking Republican on the Senate Health, Education, Labor and Pensions Committee, said through a spokeswoman that he would consider eliminating some annual testing when Congress rewrites No Child Left Behind.

But John White, Louisiana’s superintendent of education and a member of the Council of Chief State School Officers, said annual testing is a civil rights necessity.

“We should always be conscious we still have a country and a society that is rife with injustices,” White said. “We must commit to an annual measurement of our delivery of an education so we can lay bare the honest truth as to whether we’re succeeding in educating every child.”

Correction: An earlier version of this story incorrectly described how test scores are used to evaluate schools under No Child Left Behind. The scores are used to evaluate schools and to punish those that failed to meet performance goals set by the federal government. The story has been updated.