The mother said she learned of the allegations involving her son’s teacher from Gwinnett County police.
The teacher has not been charged, so WSB-TV did not identify her by name.
The mother said her son told investigators that he had sex with his 25-year-old teacher off campus, three different times.
The son said they met twice at the teacher’s home and once at the student’s home while his mother was at work.
“She wasn't tutoring my son. She came here with a specific purpose and that was to have sex with my son," the mother told Regan. “She’s a predator.”
The teen's mother said her son, who is 18 now, was 17 at the time of the alleged incident.
She said he had kept the relationship secret, not wanting to get the teacher in trouble.
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Investigators said they took notice after social media postings from other students come to light. Investigators then reviewed video from inside the school.
Police called the son in for questioning, and that’s when he revealed the relationship, his mother said.
“I said, ‘Babe, this is not your fault. You will get through this,’” his mother told Regan.
She said her son earned a scholarship to college and is hoping he can move on from this.
The mother said the teacher, who has since resigned from Archer High School, should be held accountable for manipulating her son and abusing her authority over him.
“What she did was cross the line,” the mother said.
The school district sent Regan a statement, saying: “We are aware of a Gwinnett County police investigation into allegations of an inappropriate relationship between a teacher and student."
A letter that was sent home to parents about the situation said, in part: “This type of alleged behavior between a teacher and a student is unacceptable. While this is not a situation we have experienced at our school previously, one time is too many. Ethics matter, and the trust our community places in its educators matters to Archer and to Gwinnett County Public Schools.”