As an English teacher, one of my limitations is teaching students a dialect of English I know nothing about. British English and Australian English can sometimes sound as foreign to me as different languages; that's how much variety exists within the English speaking world.
Canadian English might seem exactly the same as American English, but there are many Canadian words and expressions that would leave Americans scratching their heads. Our accents are also different, though you need to have a trained ear to hear the variations. Here's a fun little article to test your knowledge of Canadian terms and expressions.
How well do you speak Canadian, eh?