From a fellow self taught Canadian designer who is 6 years behind Andrew– I think you should reconsider his question. Because even if you want to study Art in general, the hard truth I've learned is that it's hard to focus on two things at once. If you want to become a design "rockstar" it takes 100% focus, at least in the beginning.

Perhaps look at it this way:

I quit my job to start a design agency 3.5 years ago. I would still be in school. Instead– I've bootstrapped a company, taken venture capital, lost my company, went through a lawsuit, got 100% ownership back, and rebuilt it again from scratch.

I can't tell you what's right or wrong, but I have a feeling they don't teach you that kind of street skills in school. Trial by fire.

An alternative idea– If you're parents are planning to buy your tuition in cash, consider having them invest that money into a small ad campaign over a 2-4 year agreement with $25-50/day. You could live in their basement to keep your overhead low. If you put your mind to it for 4 years straight reading conversion/marketing blogs like Quicksprout, and books like The Four Hour Workweek, you will succeed. It sounds like you're already good at picking skills up via Google.

Just an alternate route to consider. Good luck man.