Antolak was suspended with pay in November after allegations surfaced about an ineligible player on the varsity football team.
The team was forced to forfeit games after it reported the problem to league officials and was knocked out of postseason play.
Court documents filed as the team tried to get itself reinstated for playoff games said the student in question allegedly got "A's" for classes he never attended and a "F" in English that was allegedly changed to a "C". There were also suspensions that were supposedly "expunged."
A news release sent out by the Cumberland County school system Monday said an investigation was complete and that Antolak had resigned, but didn't go into details. It said her resignation was submitted March 5.
The release said the school's new principal would be contacted to "correct individual student situations over the coming week." It also said the district will be preparing a report for submission to the North Carolina Department of Public Instruction.