My advanced video students recently finished a project in rotoscoping, which was a highly labor intensive but ultimately rewarding experience for all of us. If you've access to computers and a camera, it is a great project - especially for those students who are invaribly finished days early. Because it is so labor intensive, it's better to come back to it every once in a while. A great example of rotoscoping is the movie "Waking Life" by Richard Linklater, which was filmed on a digital camera and then each frame was digitally painted. The website for Waking Life has a great little explanitory video.

And here are some really interesting outside the box examples of rotoscoping:

Artist Krišs Salmanis created a rotoscope by videotaping himself walking, transferring his stills into stencils, taking pictures of his stencils around his town, and finally creating an animation of his graffiti in sequence.

Artist Gregory Barsamian makes rotoscoped sculptures!

Caution: There are scenes in "Waking Life" that might be inappropriate for your class, Salmanis' video involves graffiti on public property, and one of Barsamian's sculptures may be unsuitable for younger viewers. Once again, use these examples at your own discretion.