You might be aware, but since you didn't say one way or the other...
Check out the education store. If you're at a recognized college or university, you'll get a great discount on Apple products (probably better than a coupon). The Canada education store can be found by following this link.
Yeah, I am already using the educational discount because I am a full time university student, but I still would not mind getting a promo code so I can maybe buy a new bag. I mostly have to buy everything like router, mouse, bag, printer and computer cause I will probably be moving soon for work and I actually gave my other computer to my mother because her`s was almost 10 years old.