In recent years, Atlanta Public Schools administrators monitored how many students failed classes and insisted on fewer F’s.

But when more than 7,700 student grades were changed over the past three years, about a quarter of them from failing to passing, no one in the district’s central office checked that the changes were justified.

This took place amid the investigation and criminal prosecution of Atlanta educators accused of cheating by changing answers on state tests. Some testified they cheated because of pressure from supervisors to raise test scores.

Superintendent Meria Carstarphen, one year into her job, has launched an investigation into grade changing and implemented policies to control it. But she said she is still trying to change a culture where doing the right thing isn’t always the norm.

In February, associate superintendent for high schools Timothy Gadson emailed principals to say he was concerned about the “staggering number” of students who earned grades below 50. He sent a school-by-school list of the number of students who received sub-50 grades.

“You should have conversations with your teacher[s] about this trend,” he wrote.

Although district policy required Gadson to be notified of any grade changes, those notifications never happened, Gadson said.

Gadson told The Atlanta Journal-Constitution he meant school staff should be talking about making sure students learned and received help, not about changing grades.

After the AJC and Channel 2 Action News reported in May about allegations of grade changing at a South Atlanta high school and allegations of other improper grading practices, Carstarphen sent South Atlanta School of Law and Social Justice Principal Charlotte Davis a letter saying her contract would not be renewed. Davis later resigned.

Carstarphen promised better oversight of grading practices and ordered a district-wide internal investigation. A final report is expected later this month.

Thus far, the district investigation has not uncovered additional cases of possible wrong-doing, APS accountability chief Bill Caritj said.

“We’ve seen mistakes but I haven’t seen anything that looked deliberate,” he said.

Both Carstarphen and her predecessor, former superintendent Erroll Davis, said they were aware of previous reports that principals had changed failing grades or pressured teachers to do so.

“The challenge at APS is always that no investments have been made over the years in control systems and feedback systems which give you early indications of these kinds of things,” Davis said. “So you only catch them through audits or when someone decides to be a whistleblower or something like that.”

And yet Principal Charlotte Davis remained in place for nearly a year after district investigators first learned of allegations that she changed more than 100 student grades from failing to passing with scant justification at the end of the 2013-14 school year.

During the next school year, the school again saw more than 100 numeric grades changed from failing to passing, a rate that far exceeded other Atlanta high schools.

Carstarphen has promised that future investigations into allegations of improper grade changing will be completed more quickly.

APS policy in effect until this October generally limited grade changes to two circumstances: Data entry errors and grade increases when a student who would otherwise have received an F completed work specified in a written academic contract.

About 3,500 APS high school grades were changed during the 2013-14 school year. That includes grades that were raised, lowered or changed from incompletes or other notations into district-required numeric grades. That works out to a per-student rate approximately 30 times greater than Dekalb County high schools.

But the districts are closer when it comes to changing failing grades to passing. In Atlanta, about one grade change in three turned an F into a passing grade. In DeKalb, that figure was about one grade change in four.

(Other metro Atlanta school districts said they were unable to provide complete grade-change numbers.)

Many of the Atlanta grade changes were due to updated marks for dual enrollment courses, changes from an incomplete to an F after parental notification, or changes when teachers offered students a chance to make up work, district officials said. In one case, a single teacher made an error in entering dozens of grades and had to correct them, Caritj said.

About 25 percent of grade changes in all Atlanta high schools in the past 3 years turned F’s into passing grades. Approximately one in five of those changes involved grades that started out below 50.

About 2 percent of all APS high school grade changes moved in the other direction turning passing grades into F’s.

Former registrar Ailisha Jones was responsible for entering grade changes at Washington High School. In her first year at Washington, 2012-13, the principals of the three academies that comprised the school had her change 50 F’s to passing grades, district records show.

The following year, Jones said she began asking for documentation for each grade change. That year, 21 failing grades were changed to passing, according to district records. And the next year, a single grade was changed.

Jones was terminated at the end of this school year, after Washington’s principal accused her of changing a student’s grade from a 69 to a 70 without the principal’s approval. Jones said she did not make the change, but it may have been part of efforts to “clean up” student transcripts.

District investigators backed the principal, but Jones believes the accusation was payback for pushing back on a culture that she says required unquestioning compliance with principals’ orders.

Atlanta has an “If I tell you, you do it” culture around school principals, Jones said. “When you question them, they make it very hard for you.”

Carstarphen said school staff will get better training to standardize grading practices across schools and reduce the number of grade changes “necessitated by mistakes on the front end.”

APS may also automate central office notification of grade changes and audit grade changes regularly.

Employees should be able to report possible wrongdoing without risking retaliation, Carstarphen said.

Four years after a state report detailed the widespread cheating problem on standardized tests, the district still faces a culture that allows unethical behavior to continue unchecked, Carstarphen said.

“It still frustrates me immensely that we have adults in the system that are still trying to game the system,” Carstarphen said. “We have to be better than this.”