Suggestions for group work?

Hey,
I was wondering if anyone had any good suggestions on how to engage my students a little more in the classroom. I've been wanting to do more group work, but I have a difficult time getting students to be interdependent. I need ideas on how students can have individual accountability while working within a group.

Treasures of The Ohio State University

In The Ohio State University Treasury of Fine Arts online gallery you can find a photograph of the OSU football team in 1890, a advertisement for the 1920 Peerless automobile, or a political cartoon published in Judge Magazine in the 1920s. The gallery features a historic collection of fine art from The Ohio State University Libraries. The collections include representative pieces from a multitude of genres: literature, the arts, the history of science, popular culture, religion, politics, and exploration. The images can be used for educational purposes by contacting the contributing University Library.