New Jersey was one of 10 states granted waivers Thursday from some of the most unpopular requirements of the federal No Child Left Behind education law.

But while the waivers were generally praised, there are concerns about what will replace the old requirements and demands that the approved states be closely monitored.

“The goals of No Child Left Behind were the right ones,” President Barack Obama said in a statement, pointing to standards, accountability and closing the achievement gap. “But we need to do it in a way that doesn’t force teachers to teach to the test, or encourage schools to lower their standards to avoid being labeled as failures.”

In exchange for more flexibility, states had to promise reform. New Jersey’s waiver calls for an overhaul of the evaluation process for teachers and principals, a new system that measures schools based on student academic growth rather than just test scores, and more choice for students in failing schools.

In a statement, Gov. Chris Christie and acting Education Commissioner Chris Cerf said that by this summer, the department will identify the lowest-performing 15 percent of schools, called Priority and Focus Schools, that would be eligible for interventions in September.

Seven Regional Achievement Centers will create customized interventions for those districts. The state will also identify Reward Schools that have made progress in closing the achievement gap between disadvantaged and minority students and their wealthier peers.

The state will introduce a new accountability system in September, eliminating the old system that required schools to make “adequate yearly progress” in 40 different areas or be labeled a “school in need of improvement.”

School officials and education advocates said a major concern is how teacher evaluations will affect students and testing.

“A lot of this was done behind closed doors,” said Stan Karp, of the Education Law Center, which has represented the state’s most disadvantaged students in the 31 urban Abbott districts. “There has been no real attention to the cost of these proposals, and the plans we do know about mean more testing for students and more intervention from Trenton. There is no flexibility from testing every child.”

He said the reforms proposed will put tremendous pressure on the most vulnerable schools at a time when the state seems to be moving away from providing funding for those schools and instead promoting more charter schools and vouchers.

“It’s a blank check to experiment on poor kids,” Karp said.

In Atlantic City, where students have made progress, Assistant Superintendent Donna Haye said some of the proposals could benefit the district, but others could present problems.

“We are showing growth on test scores,” she said. “But how are they going to incorporate testing into the teacher evaluations? That’s a major concern.”

The state has been piloting new teacher evaluation systems in 10 districts this year, including Ocean City. The Department of Education on Wednesday sent a memo to school administrators saying funding would be available for 30 more districts to pilot evaluation systems in 2012-13, and all districts will be expected to begin working toward a new evaluation system by 2013-14.

But the state system also calls for testing of some type to make up half of a teacher’s evaluation, and district officials are worried about the cost and logistics if every student will have to be tested as part of their teachers’ evaluations.

“Our teachers use the same curriculum, but the students and the test results are very different from school to school,” Atlantic City’s Haye said, citing schools that have high numbers of children who speak limited English. “How will that be addressed?”

The other nine states receiving waivers are Colorado, Florida, Georgia, Indiana, Kentucky, Massachusetts, Minnesota, Oklahoma and Tennessee.

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