At Duke, we get printed coursepacks for each class and it is usually enough to fill a 1.5' 3 ring binder. I believe there is an e-version available but I've never used it. You'll want to take lots of notes on your case materials so a printed version may be ideal.
I assume most b-schools have lockers so you can keep your coursepacks there. I usually just take out the case and some optional reading with me to class so my bag is very light.
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