HARRISBURG A controversial plan to require high school students to pass proficiency tests to graduate was approved Thursday by a divided state regulatory panel.

After hearing four hours of testimony, much of it against the Keystone Exams, the Pennsylvania Independent Regulatory Review Commission voted, 3-2, along party lines to implement the proposal.

Opponents had argued that the tests represented an unfunded mandate that would cause financial hardship for school districts without any evidence that they would improve learning.

"It is unfair and wrong to evaluate a youngster in the city of Philadelphia and other areas when proper funding is not present," State Sen. Andy Dinniman (D., Chester), minority chair of the Education Committee and a former college professor, said after the vote.

"If the funding isn't present, and help isn't to be given, it's not the student who failed, it's we, the legislature and the governor, who should be stamped with failure for not providing the resources for the schools."

Students scheduled to graduate in 2017 will be required to take biology, algebra, and language-arts tests. If they fail, they can take the tests again. If they fail a second time, they could do supplementary projects, but that would be noted on their diplomas, which opponents say would be a stigma.

The state Board of Education in September approved the Keystones as a graduation requirement for the so-called Common Core standards, a national voluntary initiative that sets proficiency requirements for kindergarten through 12th grade. The Common Core has been adopted by 45 states. When it was introduced in 2010, the Keystones were used only to identify students who needed extra help.

At the time, education officials said that the cost of providing that help would run school districts $600 per student but that it would be offset by increased state aid.

Dinniman argued that the line items in the state budget that were supposed to pay for that help "aren't there anymore." Acting Secretary of Education Carolyn Dumaresq told the panel, "I'm not being disingenuous when I say there are no new costs" associated with the new plan, which eliminates a senior-project requirement and reduces from 10 to five the total number of Keystone subject exams that could be implemented.

She and other education officials argued that schools are required to make sure graduates meet certain standards, and the way to measure proficiency is with the exams.

But Joan Duval-Flynn, education chair for the state conference of the NAACP, said the impact of the regulation could be devastating.

"Students who are pushed out of school with no diploma are regulated to lives of adversity, and it's just so very sad that these men have used their power this way," she said.

In a pilot program for the Keystones last year, one-third of students failed algebra, 50 percent failed biology, and 25 percent language arts, according to education officials. With the state dropout rate already at 25 percent, "this is serious and far-reaching," said Duval-Flynn.

Critics said local school boards could end up spending as much as $300 million to implement the tests. Poor districts that cannot afford them will not even bother, said Dinniman, and affluent districts don't want to be bothered.

Take Conestoga High School in Berwyn, which had 65 students honored by the National Merit Scholarship program and has a 100 percent graduation rate. "They're saying, what more do you want us to do? What we're begging you to do is leave us alone," Dinniman said.

Fifty-eight of 61 superintendents in Bucks, Chester, Delaware, and Montgomery Counties and the heads of four intermediate units in the region have come out against the plan.

"It's just a no-win situation," said Susan Tiernan, a member of the West Chester Area school board. "It's going to hurt the kids and is not going to prove a darn thing about what they know and what they are able to do."

Rochelle Porto, a teacher in Philadelphia, said the new requirements "are taking away from the child their individual identity."

Said Dinniman, "Perhaps we should spend on learning and not testing."