Students at an Atlanta high school had failing grades mysteriously changed to passing, much to their teacher’s surprise, back in 2011, and Atlanta Public Schools finished investigating it last September.

And an entire class at the same school — Mays High School — got passing marks after their teachers had not graded them, according to an internal district report obtained by The Atlanta Journal-Constitution this week under state public records laws.

During the intervening 3 years — while the district was consumed with a criminal investigation into cheating on state tests mostly in elementary schools — other investigations had “priority status,” investigators wrote. Meanwhile, district records show Atlanta high school staff were also under pressure to improve their schools’ stats.

After the Atlanta Journal-Constitution and Channel 2 Action News reported this spring on questions about academic integrity at several Atlanta high schools, Superintendent Meria Carstarphen ordered a district-wide review of grading practices.

“This review did not identify additional cases of serious inappropriate actions, although we did find inconsistencies in practice, lack of clarity in process, and a lack of the necessary safeguards to effectively prevent inappropriate activity,” district accountability chief Bill Caritj wrote in the review, which included Mays High School.

The internal district report shows that a Mays teacher told district investigators in 2012 that administrators would “target” teachers who failed more than 10 percent of their students and coerce them into passing more students. Investigators didn’t look into those allegations.

The same teacher also told investigators one of his students — a football player — had a failing grade of 55 he earned in 2011 mysteriously changed to a passing grade of 70. Two other students also had their grades raised.

And after a series of substitute teachers replaced the teacher for much of the 2012-13 school year, his students didn’t receive any real evaluation of their work. So an administrator decided everyone should get B’s for mid-term grades.

>>Read more about Atlanta high schools' struggles with academic integrity on MyAJC.com.