A short video describing this teaching strategy.
A student example.

As an alternative to a traditional research paper, Anne McNeil, LSA Department of Chemistry, incorporated a project utilizing Wikipedia.org to enhance her students' understanding of advanced topics in Chemistry and improve students’ scientific communication skills. Small groups of students in her graduate-level chemistry courses are challenged to collaborate on creating or revising public Wikipedia pages that will clearly communicate challenging concepts to both laypersons and experts. 

Students with different academic backgrounds are grouped to maximize available skill sets and resources within teams and to foster meaningful interdisciplinary exchanges that would otherwise be absent from the course. Groups nominate topics, and instructors select a subset based on course objectives. At key milestones during wiki page creation, both students and instructors provide critical feedback through the wiki, iteratively vetting content before the final drafts go public on Wikipedia. The public nature of final wiki pages raises student motivation, as well as the overall quality of the work. 

This project was featured on ScienceDaily: http://www.sciencedaily.com/releases/2010/08/100826122618.htm.