By Letitia Stein

TAMPA, Fla., Aug 28 (Reuters) - A Florida school district is opting out of all state-required testing, a move that experts said on Thursday sets a national precedent amid a growing controversy over the use of high-stakes standardized assessments in public education.

The Lee County School Board voted 3-2 on Wednesday to reject state-mandated testing in a district of some 90,000 students, saying it was acting on behalf "of administrators, teachers and most importantly students, whose educational growth has not been enhanced as a result of such testing."

Lee ranks as the 33rd largest school district in the nation, according to school officials based in Fort Myers in the southwestern part of Florida.

"We can sit here and roar like little kitty cats in the future and nothing is going to happen," said school board chairman Thomas Scott, who voted to reject the testing. "We have to make an impact on what is going on."

District Superintendent Nancy Graham raised concerns about the move. "This will hurt children. There is no way around it," she told school board members.

Lee appears to be the first district in the country to opt out of an entire system of standardized tests, said Bob Schaeffer, the public education director of the National Center for Fair and Open Testing, known as FairTest, which advocates against the misuse of standardized tests.

Serving a politically conservative community, the school board in Lee County appears to have been responding in part to the national controversy over the Common Core education standards.

Florida has long used standardized tests to hold schools accountable. The state was among the initial adopters of the Common Core standards, which in the past year saw some state-level modifications and is now called the Florida Standards.

An overflow crowd was overwhelmingly in favor of the vote, said Schaeffer, a local resident who attended the meeting in Fort Myers.

"Progressive educators were standing next to Tea Party activists and anti-Common Core zealots, together saying enough is enough with standardized testing overkill," he said.

What happens next is uncertain, with other Florida districts closely watching Lee's move.

The Florida School Boards Association posted an online memo outlining some potential consequences. Students may have difficulty completing graduation requirements to earn a diploma, it notes, and schools may lose various sources of state and federal funding. (Reporting by Letitia Stein; Editing by Daniel Wallis and Mohammad Zargham)