The McMichael Canadian Art Collection is located in Kleinburg, Ontario, about 35 km north of Toronto. Even though it's a hefty drive, and even though they charge you $5 to park in their ginormous (and empty) parking lot (grumble), it's totally worth the trip.
Focusing solely on Canadian art and specifically the Group of Seven, the collection is pretty vast. I thought I'd fly through, but if you really want to see everything, plan to spend at least an hour and a half. Also, it's official: my favourite Group of Seven artist is Lawren S. Harris. Swoon!
Their collection of First Nations art is really good, and I very much enjoyed the totem poles and the wood masks they had on display.
My only complaint is that they didn't have much in the way of descriptions about the art or the artists. I did a lot of looking, but not a lot of reading. An audio tour would be a nice addition.
The McMichael is definitely one of my favourite things I've done in Toronto. A must-see.
Note: they close at 4pm.