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Since some of my students are new to using technology in their teaching and learning, this element of compulsion would need to be scaffolded. For future course redesign, at the beginning of the course I could set a task for the students, as practising teachers, to investigate how forums can be used in their teaching and how they promote learning.
B. Nunes, R. Kawase, B. Fetahu, M. Casanova, and G. de Campos. Web Information Systems Engineering - WISE 2014 - 15th International Conference, Thessaloniki, Greece, October 12-14, 2014, Proceedings, Part II, page 351--364. (2014)