A retired teacher is keeping one last assignment going for his students. Bruce Farrer of Fort Qu’Appelle, Sask. is mailing letters to his students that they wrote 20 years ago, and he will continue until every last one is delivered.

Throughout his four-decade high school teaching career, Farrer tasked his students with writing letters to themselves. He kept each one so the students wouldn’t lose them or be tempted to open them before 20 years were up.

Farrer says the idea for the assignment came from his belief that people like reading old letters and artifacts, and his students might enjoy reading something they themselves wrote.

“If we find an old newspaper, we like to look at the prices and see just what was written there. If we find an old letter we tend to keep it even if the letter wasn’t written by us,” Farrer told CTV News Channel on Friday.

“So I thought it would be interesting for the students to read a letter that they themselves had written many years ago rather than by somebody else. And of course it’s pretty easy to do that if someone else keeps the letter.”

What Farrer didn’t realize was how much work would be involved in tracking down students after two decades.

“I end up turning into a detective,” Farrer said.

He takes up the task every March. While he’s retired from full-time teaching he still works, so the spring becomes a “pretty busy time for me,” he said.

What makes the job easier is that most of his students have remained in Western Canada: Saskatchewan, Alberta and British Columbia.

He has had to track a few “down east,” including a handful in Toronto. And one student moved to Taiwan.

But he hasn’t been able to find everybody. Over the years, 25 letters for students he can’t find have piled up.

“Maybe with all the publicity that this is getting some of them will be able to contact me,” he said.