Administrators at Johns Creek High School in Fulton County were investigated over allegations of improperly changing grades in math classes last spring without the knowledge or approval of the teacher.

The principal and assistant principal were accused of "unprofessional conduct" for allegedly dropping the lowest grades of students in pre-calculus and advanced math classes in an attempt to keep some of them from failing, according to a Fulton County school system report obtained by The Atlanta Journal-Constitution.

They were not disciplined, but the administrative assistant who was directed to change the grades ended up resigning.

Administrators said the grades were dropped because students were struggling in the classes, which were taught by a substitute teacher using a different way of evaluating homework than the previous teacher. The substitute resigned, and a fellow math teacher at the high school, Deborah Wallace, filed the complaint.

The report dated June 2 found neither principal Gail Johnson nor assistant principal Caren Hudson “conducted themselves in an unprofessional manner.”

Johnson is no longer the Johns Creek High School principal but an assistant principal at Riverwood International Charter School in Sandy Springs. Caren Hudson is still an assistant principal at Johns Creek.

A Johns Creek administrative assistant named in the report, Stephanie Clower, resigned. Clower, a former teacher, was Fulton County's 2010-11 Teacher of the Year. She accepted a position with another school system, according to Fulton school officials.

The personnel changes are not related to the allegations, Fulton school officials said in a released statement. The grade changes “were investigated but no evidence of misconduct was found,” the statement reads. “Therefore, no disciplinary action was warranted for any of the staff members mentioned.”

According to the report, "although their log-ins, passwords and administrative rights were utilized, neither Hudson nor Johnson made any changes to the students' grades" in the substitute teacher's grade book. Changes were made by the substitute teacher and Clower, "at the guidance and/or direction of other members of the administrative team," including Principal Johnson.

The administrators “indicated the decision to drop several of the lowest student grades was based solely on a sudden decline in student performance, a last-minute change in staff (resignation of classroom teacher in April) and changes in assessments and the way work was graded, which prompted Johnson to authorize a few of the lowest scored assignments for each student” to be dropped from the grade book, the report states.

Fulton's investigative report comes as Atlanta Public Schools face questions about improper grading practices in high schools. APS reports document allegations of grades changed from failing to passing with scant justification, employees pressured to change grades, retaliation against those who balked, and supervisors ignoring or implicitly approving signs of cheating.

State law allows administrators to change grades but says "no classroom teacher shall be required, coerced, intimidated or disciplined in any manner by the local board of education, superintendent or any local school administrator to change the grade of a student."

Fulton’s report states some students’ grades had been dropped from the substitute teacher’s grade book without her knowledge and with “no team input to make the change for the students. Wallace (the math teacher who complained) said in the past when student grades have been dropped, it has been after a team meets to discuss the issue and the team decides if students’ grades should be dropped.”

Last year, a student at Westlake High School was suspended after breaching Fulton schools' computer system and changing the grades of 15 students. The school system said the student gained access to an employee's computer and used that person's password. It said it had no evidence to suggest the staff member knew about it.