My school does use an online grading system, but I still like to have a physical gradebook. I like this hugely oversized one (on left, with my iPod next to it, for scale), because it's big enough to put actual student work into. I use plastic tabs to separate the pages into eight or nine sections, then hold the pages of each section together with a paper clip.

It's big but useful. Hopefully, like myself.

King Record Class Record Book by Elan - $7.95
Subtotal (year so far) - $115.58