Learning communities have provided adults with effective environments for professional growth and allow learners to meaningfully interact about a topic. Online course management systems (CMS) are often used to support a community of learners but do not necessarily facilitate learning communities, and specific constructivist learning activities on a CMS that increase learner sense of being a part of a learning community have not been identified. This nonexperimental study examined 146 professional educators' attitudes or opinions to identify specific instructional methods on a CMS that increase adult learners' sense of being a part of a learning community. The Sense of Classroom Community Index (SCCI) identified whether participants feel a sense of belonging to a community, and the Constructivist Multimedia Learning Environment Survey (CMLES) identified if the participant experienced constructivist learning activities: communicating, investigating, and thinking. Quantitative data was examined for measures of correlation and effect size using an ordinary least squares regression to measure the relationship of the criterion variable, scores from the SCCI measuring sense of community, and the predictor variables, scores from three sections of the CMLES regarding communication, investigation and thinking learning activities. Analysis found that there is a positive correlation of the frequency of communicating, investigating, and thinking constructivist learning activities and participant sense of being a part of a learning community. The standardized coefficient for the predictor variable B(communicating) = 0.278, t(144) = 2.39,p < 0.05, B(investigating) = 0.302, t(144) = 2.16, p > 0.05 was not significant. These results suggest a relationship between communicating and investigating learning activities and participant sense of being a part of a learning community while thinking constructivist learning activities have no significant impact. The R-square indicates that 46.1% of the criterion variable, scores from the SCCI, are explained by the predictor variables, scores from the CMLES. The results from this study can encourage instructional designers and course facilitators to use communicating and investigating constructivist learning activities more often. It is recommended that this study be used to support additional research on effective communicating and investigating constructivist activities on a CMS. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]