Police have charged Mark Jay Fox, 62, of 101 Marsburg Lane, Cary, with indecent liberties with a minor.
Authorities say they have reason to believe Fox "inappropriately touched" a girl on more than one occasion.
Wake County Schools confirm Fox worked at East Cary Middle School since the fall of 2009. According to the school's website he's an in-school suspension teacher.
Police say the victim didn't attend East Cary Middle, but warrants say the inappropriate touching happened when the child was placed in a teacher assistant-student relationship with Fox.
They say the crimes took place over the course of several months in a residential setting and that one of the child's parents notified authorities.
Just after 4 p.m. Wednesday, detectives served a warrant and talked to Fox inside for more than an hour before arresting him.
Hours later, he appeared before a magistrate. The magistrate set Fox's bond at $100,000. His first court appearance is scheduled for Thursday morning.