If you count imports, I’m pretty sure every version of “Degrassi” Canada’s ever pumped out has ended up on American TV.
But that’s very distinct from an American network setting a show about high school life in Canada. Imports of shows are common because it’s cheaper than producing your own; apparently they’re selling another Canadian show, “Little Mosque on the Prairie,” to a US network. It’s easier for a US carrier to just buy that show than to produce their own version set in Kansas which would be only 2 percent different anyway. Why spend time and money producing a copy when in a week you can buy a few dozen ready-to-air episodes?
What would never happen is a US network coming up with an idea and saying “Let’s base this in Canada/Australia/England” or whatever. Why would they, anyway? It just adds expense and possibility of error.