This document discusses learner participation and engagement in massive open online courses (MOOCs). It presents research on how the open nature of MOOCs leads to high dropout rates. The document outlines several hypotheses about factors that influence learner engagement, including personal characteristics and course design elements. It then describes the design of two MOOCs - one using only online elements and one blending online and offline interactions. Learner engagement and participation metrics like posting and interaction rates were higher in the blended MOOC compared to the purely online one. The document concludes that MOOC learner motivations differ from traditional students and that course design can impact engagement levels.