A teenage student who allegedly had sex with his teacher wanted to kill himself after gossip about the event began spreading through his school, a Kitchener court heard Tuesday.

Jacqueline Lavigne, a teacher on leave from Monsignor Doyle Catholic Secondary School in Cambridge, is on trial for sexual exploitation.

She has pleaded not guilty.

Crown prosecutors allege Lavigne had sex with a then-17-year-old student in 2011.

A friend of that student testified Tuesday that she, along with Lavigne, the complainant and five or six other students, were part of a BlackBerry Messenger chat group.

That group started out as a way to talk about a sport, the student testified, but conversations eventually turned toward the personal.

The student said she recalled messages and personal conversations in which Lavigne asked the complainant about his relationship with his girlfriend.

On one occasion, she said, she saw Lavigne write a school assignment for the complainant.

“She was typing, saying ‘I’m doing his essay,’” she said.

The student on the stand said she first heard about the alleged sexual encounter in January 2012, while at a party.

She talked to the complainant that night, and again on the phone the next day.

“He wanted to commit suicide. He was crying,” she told the court.

The trial will continue tomorrow with testimony from a BlackBerry employee analyzing the alleged contact between Lavigne’s phone and the phone of the complainant.