I don't know how many OS X users there are in the class. If there's more than one, I'd encourage you to use Rendezvous to connect in class and make use of some tools to enhance your classroom experience.

• You can use iChat with Rendezvous to open up chat sessions with others in the class. I think this kind of back-channel communication can be helpful.
• Download and install Hydra, a Rendezvous enabled editor. You can use it to create a set of group notes. Once you use it, you'll be hooked.