Although much is now known about how students learn, little is known about the process by which computer-assisted, cutting-edge teaching and learning materials and practices are diffused and brought into the undergraduate classroom. In May 2010, the American Sociological Association (ASA) launched a new Teaching Resources and Innovations Library of Sociology (TRAILS). In this comparative evaluation of the first year of the diffusion of TRAILS, we ask, how did the use of this new technology diffuse? And did it diffuse beyond the scope of users of an earlier paper-based library of materials? Our evaluation research suggests that diffusion has occurred through a homophilious network, opinion leaders are the most influential in spreading information, and the diffusion pattern was not the normal and expected S-shaped curve. Social interventions are necessary to increase diffusion beyond an existing social network. The evaluation uses a multi-method model of data collection and analysis.#interventions #technology #Assessment #networks #2012Conference #diffusion