Paul Clifton Canally, 31, had faced more than 150 years in prison plus eight additional life sentences. In the plea deal, a judge sentenced him to a minimum of 50 years and a maximum of 60, while telling him he violated the trust of parents and students.
Prosecutors said he abused seven boys in all. The parents of all seven were in court Monday and some spoke during the hearing.
Canally also spoke, telling his victims he is sorry.
"I wish I could take everything back but I can't and I wish I could say or do more but I don't think there's anything more that can be done. All I can do is apologize," he said. "I am so sorry. You trusted me and I betrayed that trust. If I could take it back I would , I wish I could do so much more but I can't."
Canally could get more jail time for a pending charge in Pennsylvania if he's convicted there.
Canally worked as a teacher at Archer Lodge from August 2007 to July 27, 2009. All but one of his alleged victims were students at the school.
Detectives first arrested the former science teacher in February 2012.
Canally resigned his teaching position in the summer of 2009 after the Johnston County School district began investigating a complaint against him. A district spokesperson told ABC11 last year that the complaint was not of a sexual nature, but did not elaborate.