Santa Rosa City Schools Superintendent Sharon Liddell announced Friday she will resign effective June 30.
Liddell, who turns 65 next month, has been with Sonoma County's largest school district since 2003. She became superintendent in 2005.
"This is something I have been thinking about for a number of months," she said. "I have some goals I'd like to achieve."
Liddell said she has been in contact with employment search firms and is considering moving to a larger school district or possibly teaching at a university.
The seven members of the school board were notified of Liddell's decision Feb. 8. District administrators were told Thursday and a letter was distributed to all staff members Friday afternoon.
"So far, just walking down the hall and hearing people talk about it, there is genuine surprise," said Andy Brennan, president of the Santa Rosa Teachers Association and a teacher at Santa Rosa High School.
Although students across the district have made academic gains since 2005, they have not been enough to keep the district out of three consecutive years of federal sanctions under the No Child Left Behind law.
Liddell's tenure also has been marked by dramatic budget cuts, but board vice president Bill Carle said other districts have faltered under similar conditions.
"There are other districts that imploded, that found reasons to infight," he said.
Santa Rosa City Schools did not, he said.