I came across another framework called the Adolescent Community Engagement (ACE). While COI is more geared to adult learners, the ACE – an acknowledged derivative of COI – is geared toward K12 online learning. You will see similarities in the concepts presented.
Borup, J., West, R. E., Graham, C. R., & Davies, R. S. (2014). The Adolescent Community of Engagement framework: A lens for research on K-12 online learning. Journal of Technology and Teacher Education, 22(1), 107-129.
