VICTORIA - A high-society Montreal matron and her son are found dead in the bedroom of the woman's mansion. Two gunshots were heard. Three bullets are recovered. The year is 1901.

Outdoorsman and iconic Canadian painter Tom Thomson goes out for a paddle in Ontario's fabled Algonquin Park and disappears. His body is found floating in Canoe Lake days later. Murder or misadventure? The year is 1917.

A Canadian diplomat, removed from a post in Japan and made ambassador to Egypt, jumps from a rooftop. He'd been the target of persistent allegations of communist sympathies and ties to the Soviets. The year is 1957.

These three unsolved mysteries have been deemed interesting enough to be selected as the final three "cold cases" being added to a popular interactive Canadian history website.

"History is too important to be boring," says Dr. John Lutz, a historian and co-director of the Great Unsolved Mysteries in Canadian History project, based at the University of Victoria.

It's hard getting most students interested in history, especially Canadian history, he said.

"We realized that the problem was often the way we do it, by trying to cram dates and names into their heads. But that's not really history, it's just the context."

"Doing history is actually about solving puzzles and solving mysteries."

Ten years ago, he and another British Columbia historian, Ruth Sandwell, came up with the idea of putting intriguing mysteries on the web.

"We thought by putting the evidence up there for the students to solve themselves, we could hook them on history. I think we've been successful."

Since 1997 the project has taken off, garnering funding and winning awards for the way it has presented a collection of unsolved mysteries for university and high school teachers and their students.

Currently there are nine complete cases available.

They include the stories of a legless, mute man who washed up on a Nova Scotia beach in 1863 - and lived another 50 years; the hanging of an aboriginal man accused of killing three black men on B.C.'s Saltspring Island in the late 1860s; the torture and confession of a young slave accused of setting the Montreal fire of 1734 and the massacre of the Black Donnellys in rural Ontario in the 1880s.

In each case, Lutz says the team involving about 30 historians and researchers at universities across Canada, just writes the first paragraph.

Students are then encouraged to use the websites, which are designed to mirror an actual archive, and dig through the evidence to put the pieces of the puzzle together.

Extensive use is made of audio and video, and in some cases, three-dimensional imagery, to recreate the so-called "scene of the crime."

In the oldest unsolved mystery, Where is Vinland?, the new technology helps students try to determine whether a site in Newfoundland really is the settlement founded by Vikings 500 years before Columbus.

"Because the data is so excellent from archeological work, we've been able to recreate the L'Anse aux Meadows viking village in 3-D," Lutz said, adding software is available to allow history sleuths to move around the site.

He said the website gets about 16 million to 17 million hits annually. Teaching guides are available for download at no charge.

"We know that it's being used in about 2,000 classrooms around the country and about nine or 10 different countries as well," he said.

In addition to the more complex cases, the team also runs a companion site aimed at middle and junior high schools.

The website at www.mysteryquests.ca has more than 20 simpler cases designed to hone the detection skills of younger students aged 11 to 18.

With a grant of $450,000 from the Department of Canadian Heritage, the team is adding the final three mysteries, which should be ready by the spring of next year.

The first, being developed by a pair at McGill University, involves the apparent murder-suicide of Montreal's Ada Redpath and her son Clifford in June 1901 in her mansion.

The second is the story of a controversial diplomat's untimely death. It's being prepared by a colleague of Lutz's at UVic.

Herbert Norton apparently took his own life by flinging himself from a Cairo roof in April 1957 after a U.S. Senate subcommittee accused him of being a spy for the Soviet Union.

And the third and most famous case is being worked on by a historian at Toronto's York University. It involves Tom Thomson, regarded as the founder of Canada's Group of Seven, who died in "suspicious circumstances" in July 1917 on a lake he knew like the back of his hand.

"Could he have accidentally drowned in a calm lake on a sunny day or was something more nefarious at play?" Lutz pondered.