Reflection is a cornerstone of most teacher education programs, but common practices have long been individualistic and this has become increasingly evident in an era when young people are participating in online cultures more than ever. Informal participation in digital affinity spaces could provide insights for more formal learning environments. We encouraged collaborative reflection among 77 middle/secondary pre-service teachers using the closed social networking site Edmodo. While there were obstacles and ambiguities, findings indicated that our pre-service teachers found the site highly usable, appreciated the choice and influence afforded them through the medium, and grew as teacher-candidates from peer-to-peer interactions. (C) 2014 Elsevier Ltd. All rights reserved.