It requires a lot of energy to support the adoption of online learning by adult learners. Thus, the question of how online learning intersects with adult learning may provide meaningful pathways to understanding online learning per se. This study aims to understand the online study behaviors of teachers enrolled in an online Educational Technology Master's program. This case study involved a Research Methods course, which was part of an online project for teachers. An online control list form and interviews were used as data collection tools. The results indicated that sharing, problem solving, product development, monitoring, and research were prominent activities that shape the study behaviors. While some of the behaviors in these activities indicated the reshaping of previous study behaviors, other behaviors newly appeared during the program. Characteristics of adult learners, online setting features, and the context of the projects were the main factors that influenced study behaviors. Finally, the implications for better online adult learning experiences are addressed.