AUGUSTA — The resignation in Florida of a close ally of Maine Education Commissioner Stephen Bowen and Gov. Paul LePage has prompted a new round of criticism of some of the administration’s initiatives, including a controversial A-through-F grading system for Maine’s public schools.

According a Reuters news service report, Florida Education Commissioner Tony Bennett resigned on Thursday over what he called “malicious, unfounded” reports that he rigged the grade for a charter school run by a major campaign donor during his previous job in Indiana.

Bennett, who took the Florida job in January, said the allegations that he raised the grade of an Indiana charter school at the request of an influential Republican donor who runs the school, are inaccurate.

“It’s not fair to the children of Florida that I continue as commissioner and deal with the distraction,” said Bennett, who said that he intervened in the school’s grade to correct a statistical anomaly that unfairly penalized some Indiana schools. He said he has asked for an investigation into the matter.

“I am fearless about what they will find,” said Bennett to reporters.

Bennett was the keynote speaker at a “Putting Students First” education summit organized by LePage on March 22 in Augusta. Bennett created and implemented school grading systems in Indiana and Florida similar to one unveiled in Maine on May 1 that has been widely criticized by educators and lawmakers, particularly Democrats.

Lois Kilby-Chesley, president of the Maine Education Association, the union that represents Maine public school teachers, said in a prepared statement Thursday that corruption in the state’s school grading system is one reason she and others opposed it to begin with.

“The Maine Education Association hopes that Maine will not follow Florida’s Commissioner of Education, Tony Bennett, down the crooked path to school grading,” said Kilby-Chesley. “Having heard Mr. Bennett present at Gov. LePage’s forum on education this past spring, we recognize that his values do not represent those of Maine citizens. His most recent entry into the news for allegedly changing school grades is an example of the MEA’s greatest fears about the grading of schools.”

The grading system is part of LePage’s school reform agenda, which proved to be a major partisan battleground during the recently concluded legislative session. Democrats harshly criticized the grading system and said they were planning one of their own. Sparring between LePage and Democrats over how the state’s public education system should function continues, most recently with a blowup this week between the governor and Senate President Justin Alfond, D-Portland, over an event at a charter school in Portland.

Bowen, who is involved in an education reform group called Chiefs for Change, was quick to defend Bennett in a prepared statement on Thursday.

“Tony Bennett is a trailblazing education leader whose efforts to innovate and improve student outcomes remain a model to the nation,” said Bowen. “Reform isn’t easy, but as Tony knew, those who are content with the status quo will always push back against new approaches and new ideas. Nevertheless, improving outcomes for our children make the hard work and the political potshots that come with it more than worthwhile.”

Bowen also addressed renewed criticism about Maine’s school grading system, which gave as many schools D’s and F’s as it did A’s and B’s.

Bowen said the grading system isn’t prone to corruption because it is based on data and test scores that are firmly in the public realm. The next round of report cards for elementary and high schools will be released in the spring.