As online learning enrollments rapidly increase, it is vital to explore effective course designs that deepen students' learning experiences. This multiple-case study explores four online courses at Brigham Young University–Idaho that include learning activities where students learned through Teach One Another activities. Teach One Another is similar to Reciprocal Peer Learning where students simultaneously learn and contribute to their peers' learning. Findings across the cases of this study show that Teach One Another activities in online courses encourage students to be accountable and motivated to complete individual course work as well as group assignments. As students learn to build trusting learning relationships, group activities may deepen students' learning experiences. This study discusses implications for online course designers, developers, and administrators who are interested in giving students opportunities to deepen their learning of the content and develop life skills such as accountability, responsibility, and trust.