Over the last decade, a citizen science movement has tried to engage students, laymen and other non-scientists in the production of science. However, there has been less attention in citizen science projects to use the public to disseminate scientific knowledge. Wikipedia provides a platform to study engagement of citizen scientists in knowledge dissemination. College and university students are especially appropriate members of the public to write science articles, because of the course-work and mentorship they receive from faculty. This paper describes a project to support students’ writing of scientific articles in Wikipedia. In collaboration with a scientific association, we involved 640 students from 36 courses in editing scientific articles on Wikipedia. This paper provides details in the design of the program and our quantitative and qualitative approaches to evaluating it. Our results show that the Wikipedia classroom experiment benefits both the Wikipedia community and students. Undergraduate and graduate students substantially improved the scientific content of over 800 articles, at a level of quality indistinguishable from content written by PhD experts. Both students and faculty endorsed the motivational benefits of an authentic writing experience that would be read by thousands of people.