These videos on the Principles of Design from Ctrl+Paint are, hands down, some of the best explanations that I've ever seen. I'm sure these will become a mainstay in my classroom. I don't even like teaching about the E&P's; on any given day I'm going to lean more towards incorporating Oliva Gude's Postmodern Principles in my class.  However, as modernist as these ideas are, good design is good design, and for my money Matt Kohr explains these concepts with clarity, simplicity, and elegance.  Using fantasy subjects to illustrate his point, these videos appeal to both my inner art geek, and my inner... well, traditional geek.

Matt has a whole library of stuff outside of Design as well, some that has to do with digital painting, which is his focus, and some which is applicable to a broad range of art forms. 

I'll hook you with his video on Balance, here, and then you can head over to Ctrl+Paint for the rest of the videos. 
CtrlPaint - Principles of Design: Balance from matt kohr on Vimeo.