Social media (SM) support new approaches to learning that rely on voluntary, peer-to-peer communication using devices and software provided and managed by students rather than on institutional course management systems. We present one case of such an approach with first-year university students (n = 86) in Thailand using SM for asking and answering questions between peers in a face-to-face computer-programming course. Encouraging students to ask questions about course content can result in improved performance. In general, understanding how students participate and what drives them to participate can provide insights into how universities and instructors can be socially ready. Students used SM during 10 weeks of an 18-week course. Each of four sections selected one form of SM as follows: Facebook [n = 33], Instagram [n = 21], Twitter [n = 21], and Line [n = 11]. The mixed-methods case study involved quantitative measures of how students participated and quantitative and qualitative measures of students' perceptions of what drives or discourages their participation. Results revealed patterns in participation as follows: participation and motivation; passive and active participation; participation and sample size; participation and type of SM and; participation and student demographics. Implications for practice relate to the value of instructors' understanding of the social incentives for student participation such as social recognition, gratification of needs and convenience. Implications for research focus on the value of investigating new forms of participation available to read-only participants and 'lurkers' using features of SM such as 'liking' and sharing.