Atlanta schools superintendent Meria Carstarphen says the district will make changes to prevent school principals and other district employees from improperly changing students’ grades.

Her comments in an interview Thursday came after The Atlanta Journal-Constitution and Channel 2 Action News reported on more than 200 instances of improper grading practices, including unjustified grade changes, at at least four high schools over the past several years.

In one of the cases, Atlanta Public Schools took nearly an entire school year to investigate a principal accused of changing, with scant justification, 144 grades from failing to passing. The principal remained in her position for most of the 2014-15 school year.

Carstarphen said Thursday that delay was “unacceptable.”

“I want them done in 30 days or less,” she said of similar internal investigations.

Carstarphen became superintendent last summer, after many of the alleged improper grading practices took place. She said she was briefed then on the allegations.

“The outgoing superintendent, who had been here for 3 years, wasn’t saying that we had a flawed process,” she said.

Carstarphen said the district will now give educators clearer instructions about when it’s OK to change a student’s grade.

Real-time monitoring of grade changes could help flag future problems early. But that’s not something APS’ creaky data systems can handle now, Carstarphen said.

District staff are conducting an internal review of grade changes. Results from that review are expected before the start of the coming school year.

“I’ll be cleaning it up again after we learn more,” Carstarphen said.