Originally Posted by
MK313
If you're used to using a backpack currently & it's working for you, another alternative is to strap the backpack to a rear rack. I use a Mountain Hardwear pack strapped down with Surly Junk Straps. Works great for me and it's great for once I get off the bike as well. As your bike will be with you all the way into the classroom, that may not be as big of a concern.
Thought about that, I am currently using a dueter backpack and it is pretty compact. I would like to be able to carry student papers or the odd text home with me and my current pack does not seem big enough...especially if I strap it down to something. However its something to certainly consider.