Police say the charge stems from an alleged relationship between the teacher and a male student at Edmonton Christian High School between September and December 2004.
The student's age at the time has not been released.
Harvey James Klok, 47, is charged with one count of sexual assault. He was released on bail earlier this month and is to appear in court July 3.
Police would not say when he stopped teaching.
Det. Barb Clover says officers travelled to Newfoundland to escort Klok back to the city.
"I don't want to get into the specifics of the case, because it is very personal for the victim, but he was a teacher of this student," Clover said Monday at police headquarters.
"It was very difficult for him to come forward as it is, so we want to keep the confidentiality that he had. It's a very private thing and a lot of times there's still a lot of victim blaming, no matter how old the person is, and I don't want to see that happen in this case."
Clover said the complainant came forward a year ago.
"There's so much more awareness that he felt comfortable coming forward and reporting that now," she said.
"That's a really big step considering that there could be other victims out there. A lot of times what people need is for someone to step forward first and then they feel comfortable that they can come forward as well."
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