Sloan-C. — Publishes annual reports on growth and other aspects of online learning. Access the list at http://onlinelearningconsortium.org/publications/annual-surveys.

U.S. Department of Education Study (May 2009) — Evaluation of Evidence-Based Practices in Online Learning, a Meta-Analysis and Review of Online Learning Studies finds “that, on average, students in online learning conditions performed better than those receiving face-to-face instruction.”