TALLAHASSEE -- The resignation this week of Florida’s top education official brings to an end a short one-year run marred by a public outcry over testing, declining FCAT scores and charges that the state moved too fast this year to change its testing system.

In a letter submitted late Tuesday to Gov. Rick Scott, Education Commissioner Gerard Robinson said it had been an honor to serve during an "unprecedented period in the history of school reform."

Robinson made no mention of recent criticism or missteps by the state Department of Education, instead alluding in his letter to the distance between him and his family in Virginia. His wife, a law professor, hadn’t found a tenured position in Florida.

Robinson’s resignation is effective Aug. 31.

Members of the state Board of Education, who now must find his replacement, said they were surprised by the announcement.

But Robert Martinez, vice chairman of the board and an occasional critic of Robinson’s performance, said he respected Robinson’s decision.

"Family is paramount. If I were him, I would do the same thing," he said.

Rumors have swirled for months that Robinson was on his way out. But Scott and the state board seemed to stand behind him.

On Wednesday, speaking briefly to reporters at the airport in Tallahassee, Scott praised Robinson and said he was "sad" to see him leave his administration.

"I don't think that's an easy job. He worked hard at it. He cared about students. He cared about measurement,” Scott said. “He listened to parents. I think he did a good job."

Kathleen Shanahan, chairwoman of the state board, said, "The board is extremely grateful for Gerard’s leadership this past year."

Robinson became Florida’s top education official in June 2011, after the resignation of former Commissioner Eric Smith, who had the job for about three years. Where Smith appeared to clash with the governor, Robinson was Scott’s choice for the job. As Virginia’s education secretary, Robinson had pushed school choice options, including vouchers, and said he supported merit pay for teachers.

As Florida’s education commissioner, Robinson has been aggressive about pushing for higher academic standards and raising the bar on the state’s standardized tests, moves that caused an unprecedented decline in tests scores and increased the number of D and F schools statewide. And in July, the state had to admit that more than 200 school grades were wrong — state officials had messed up their own grading formula.

Robinson has traveled statewide to public forums to quell rising frustration among many parents, teachers and school leaders. But he has been criticized heavily for sounding tone-deaf in the face of growing testing fatigue, blaming school districts — not the state — for the amount of testing in schools.

Rita Solnet, a Boca Raton activist who has played a prominent role in Florida’s anti-testing movement, said she didn’t view Robinson as a long-term leader but rather "he was the guy who was going to come in, execute the most egregious changes possible, be the fall guy and leave."

At a national teachers union conference in Detroit this past week, Solnet said comments were circulating that Robinson was on his way out because former Gov. Jeb Bush wanted to stem criticism against a testing system he helped create and still champions.