Authorities say John Martin had hours of video footage from the pinhole cameras and kept video screenshots on his cellphone.
Martin resigned last week from Gloucester Catholic High School in Gloucester City, near Philadelphia.
He turned himself in on Wednesday and was ordered not to go near the school or its students or staff members. He's charged with invasion of privacy. A woman who answered the phone at his home in Wenonah hung up on a reporter.
Investigators are contacting everyone who appears in the videos, mostly girls and women.
Principal John Colman says the security of students is his most important obligation.