In just five months, the Obama administration has freed schools in more than half the nation from central provisions of the No Child Left Behind education law, raising the question of whether the decade-old federal program has been essentially nullified.


On Friday, the Department of Education plans to announce that it has granted waivers releasing two more states, Washington and Wisconsin, from some of the most onerous conditions of the signature Bush-era legislation. With this latest round, 26 states are now relieved from meeting the lofty — and controversial — goal of making all students proficient in reading and mathematics by 2014. Additional waivers are pending in 10 states and the District of Columbia.


“The more waivers there are, the less there really is a law, right?” said Andy Porter, dean of the University of Pennsylvania’s Graduate School of Education.


While No Child Left Behind has been praised for forcing schools to become more accountable for the education of poor and minority children, it has been derided for what some regard as an obsessive focus on test results, which has led to some notorious cheating scandals. Critics have also faulted the law’s system of rating schools, which they say labeled so many of them low performing that it rendered the judgment meaningless.


In exchange for the education waivers, schools and districts must promise to set new targets aimed at preparing students for colleges and careers. They must also tether evaluations of teachers and schools in part to student achievement on standardized tests. The use of tests to judge teacher effectiveness is a departure from No Child Left Behind, which used test scores to rate schools and districts.


Congress has tried and failed repeatedly to reauthorize the education law over the past five years because Democrats and Republicans cannot agree on an appropriate role for the federal government in education. And so, in the heat of an election year, the Obama administration has maneuvered around Congress, using the waivers to advance its own education agenda.


The waivers appear to follow an increasingly deliberate pattern by the administration to circumvent lawmakers, as it did last month when it granted hundreds of thousands of young illegal immigrants a reprieve from deportation. The administration has also unveiled policies to prevent drug shortages, raise fuel economy standards and cut refinancing fees for federally insured mortgages.


Critics question whether the waivers have done much to genuinely shift the focus of federal education reform, given their continued reliance on standardized tests. The waivers “should probably make the meh list,” said Joshua Starr, superintendent of the Montgomery County schools in Maryland, which was granted a waiver in May.


Mr. Starr said he believed that education reform should focus on incentives to help teachers collaborate and help students learn skills that could not simply be measured by tests.


“It is another example to me of how we’re not focused on the right things in the American education conversation today,” Mr. Starr said. “I have a lot of respect for Arne Duncan,” he added, referring to the secretary of education, “but it’s just sort of moving around the chairs on the Titanic.”


Mr. Duncan, in a telephone interview on Thursday, said states that had received waivers, including New York, New Jersey and Connecticut, would also use a mix of other indicators to evaluate teachers and schools, like how many students actually enrolled in college or took Advanced Placement exams, as well as reviews of teachers by their peers, their students and their principals.


“You have to look at multiple indicators and multiple measures,” he said. “There’s been historically a push to way oversimplify what is very complex.”


House Republicans have repeatedly protested the Obama administration’s use of waivers as an end-run around Congress.


In a speech to the American Enterprise Institute this year, Representative John Kline, a Minnesota Republican and the chairman of the House Committee on Education and the Work Force, accused the administration of using waivers “in exchange for states adopting the policies he wants them to have.”


But education officials in the states that received waivers expressed relief from the pressure of the looming 2014 deadline.


“There was a general feeling that there were these goals that no one was ever going to meet,” said Kelli Gauthier, spokeswoman for the Tennessee Department of Education. “Now we have standards that are possible.”


Instead of labeling all struggling schools as failing, the waivers direct states to focus most attention on the bottom 5 percent of low-performing schools. “With the waiver we can focus on those schools that really need a lot of help,” said June Atkinson, North Carolina’s state superintendent of public schools.