Correction: A previous version of this article incorrectly identified Fairfax County School Board member Daniel G. Storck as the board chairman. Ilryong Moon (At Large) is chairman.

More than 40 percent of the instructional staff at Fairfax County’s Fort Hunt Elementary packed up their classrooms and left for new jobs over the summer, part of what parents and teachers say is a response to a toxic work environment at the school near Mount Vernon.

Teachers, parents and staff said in interviews that morale at the 600-student school reached a low point during the past school year. Teachers said they are afraid to voice their opinions to school leaders at meetings, parents said field trips and school events have been cut back in recent years, and students have reported not being allowed to speak during lunch.

A recent system-wide staff survey ranked Fort Hunt 138th out of 139 Fairfax elementary schools for teacher job satisfaction. JoAnn Karsh, executive director of the Fairfax Education Association, the largest teacher organization in the county, said parents and teachers at the school have told her that Fort Hunt has devolved into a “joyless place that has become a bad place for learning.”

With school scheduled to start in Fairfax County on Tuesday, Fort Hunt faces opening day with the additional challenges of incorporating a large number of new staff and trying to burnish its reputation.

After years of troubling standardized test scores, Fort Hunt will begin this school year designated as one of 29 “priority schools” in Fairfax. The priority designation will offer the school additional funding to meet testing benchmarks, but most parents and school community members view the program as a sign of a struggling school.

One parent, who spoke on the condition of anonymity because her children are students at Fort Hunt and she doesn’t want them to face repercussions, said staff divisiveness has “torn the school apart.”

Barbara Leibbrandt, principal at Fort Hunt, met with a Washington Post reporter but declined to comment for this story.

Teachers said that some of their colleagues have departed in recent years as a result of the school’s environment. Fairfax County schools officials said the turnover rate at the school after the 2010-11 school year was 22 percent; it grew to 24 percent in 2011-12 and jumped to 40 percent after this past school year, when 22 Fort Hunt staff members left.

The most recent turnover rate at Fort Hunt was more than double the rate among all 28 schools in Fort Hunt’s “cluster” within the Fairfax school system, according to John Torre, a Fairfax schools spokesman.

“Turnover occurs every year at every school,” Torre said in a statement. “We cannot discuss specific personnel matters at Fort Hunt, but teachers and other instructional personnel leave for a variety of reasons.”

Torre added that parents and teachers who have concerns about Fort Hunt “should take those concerns directly to Principal Leibbrandt, and if they are not satisfied with the response, they can bring their concerns directly to the cluster superintendent.”

The assistant superintendent for the cluster, Deborah Tyler, declined to comment.

Not everyone at the school is unhappy. Fort Hunt has a much sought-after Spanish immersion program, and parents rave about it. Families say the school generally has a talented faculty.

Some say the school’s demographics could play a significant role in the school’s faltering reputation.

School Board member Daniel G. Storck, whose Mount Vernon district includes Fort Hunt, said the student population at Fort Hunt is a mix of middle-class children from the surrounding area south of Alexandria and a large group of children who are bused in from a nearby apartment complex for low-income families.

“The parents’ concerns are real,” said Storck, who said he has spoken to the principal and other ranking school administrators about Fort Hunt. “But it isn’t as simple as people want it to be as you address the needs of a school community that are very diverse.”

Karsh said the FEA, the teachers’ organization, became involved in January after fielding several complaints from members about Fort Hunt. In late July, Karsh sent a letter to the new Fairfax superintendent, Karen Garza, about the reported problems at the elementary school.

“Several parents and teachers talked about the punitive environment in the school: No talking during lunch, no special events or celebrations,” Karsh wrote. “Teachers expressed grave concern for the way children were treated in the building.”

In an e-mail to The Post, Karsh wrote that the FEA’s goal for teachers at Fort Hunt is to restore a positive working environment.

One teacher who left this year for a new school said staff members have become anxious and unnerved at Fort Hunt, and that turning things around could prove difficult.

“The negative energy there makes your hair stand on end,” the teacher said.