sally_bradshaw.jpgTALLAHASSEE, Fla. (AP) – Amid an ongoing dispute over the future of Florida's public schools, an ally of former Gov. Jeb Bush has abruptly resigned from the State Board of Education.

Sally Bradshaw, who once served as Bush's chief of staff, resigned on Sunday. Her one page resignation letter said it was effective immediately. She said that "family obligations'' would prevent her from serving out the rest of her term, which expires at the end of the year.

That means Bradshaw will miss an important meeting this week where the board is expected to keep in place a controversial safety net policy that would limit a school's grade from dropping more than one letter at a time. Bradshaw voted against the change this past summer and said it would hide the true performance of the state's schools.

Bradshaw, like Bush, the former Republican governor, has also been an outspoken supporter of Common Core State Standards despite a growing backlash that includes some Republican Party activists. Just last month, she questioned a lack of direction from Republican Gov. Rick Scott on the standards. Days later, Scott ordered public hearings on the standards and opened the possibility for changes.

Bradshaw said her position on Common Core had nothing to do with her decision to step down.

"While I remain a supporter of Common Core, this decision was based on my family obligations and is unrelated to any ongoing policy discussions,'' Bradshaw said.

The Department of Education is holding public meetings on the standards in Tampa, Davie and Tallahassee this week. The state has already received more than 5,000 comments on the standards on a website set up for the public.

Scott initially backed Common Core standards, which set uniform benchmarks for reading, writing and math. But in recent weeks he refused to come out strongly in favor of Florida's transition to the new standards, which have been adopted by 45 states and the District of Columbia, as opposition has mounted among local GOP organizations.

The standards are a result of an initiative sponsored by the National Governors Association and the Council of Chief State School Officers. Opponents see them as the nationalization of education policy and standards, something they say should be left to the states.

The new standards are backed by Bush, who helped create the state's current A-to-F grading system while in office from 1999 to 2007. It would be a huge defeat to Bush's potential presidential campaign if his own home state suddenly changed directions on education, an area where he is seen as a leader.

The appointed board that oversees Florida's public schools has already adopted the new standards and the state is moving ahead to implement them. Elementary schools are already using the standards and the plan is to fully implement them during the 2014-15 school year.

Critics of the standards are already complaining that this week's hearings are being run in a way to continue to justify the new standards.

Education Commissioner Pam Stewart disputed that criticism. Stewart said that while she does not expect Florida to abandon the standards, she said there is a "good chance'' that the state will revise them based on feedback from parents and administrators.