The idea of Wikipedia article creation as a teaching tool is becoming more popular; for example, getting a class to create 120 articles on Roman civilisation. There are short proposals here and here, a link to an interesting email discussion which mentions student resistance to becoming an author, and a longer introduction to the process by Piotr Konieczny.
But actual reports from the front lines are always the most valuable. Jon Beasley-Murray, a fellow Duke alum, describes having his SPAN312 class write articles on Latin American literature. A lovely walk-through of the tribulations and successes, and the unexpected help of the Feature Article team. He compares it to “the usual essays and exams that we assign our students, [which] really are rather pointless busywork.” Jon also has a some helpful tips for lecturers contemplating trying this themselves—recommended reading.