Where do I get a product key and ISO for Windows 8 Boot Camp? (Please note that this is a hypothetical question as I do not yet own the computer mentioned in this post, but will be getting it next year for school)

Next year, I am going to buy a MacBook Pro Retina for school. The IST course I will be taking requires Windows for Android development. Where would I download the ISO for installing Windows 8, and where would I buy a product key? I'd like the Pro version too because I want to use remote desktop from my iPad when necessary (I already know how to do this)
Microsoft has a Student store that sells Windows 8, downloadable, with key for $69. Presumably from your post, you would qualify for academic pricing.