Computer-supported collaborative learning (CSCL) is learning that is supported by the collaborative use of computer-based technologies, wherein “collaborative” indicates that multiple students are attending to a shared goal of learning (Dillenbourg, 1999). Most instructional applications of CSCL involve collaborative learning in small groups, supported by software for inquiry, argumentation, or problem solving (Looi et al., 2008; Nussbaum et al., 2007; Stahl, 2009), but there also are many examples that involve collaboration in communities, such as knowledge building and game communities (Fields & Kafai, 2009; Scardamalia & Bereiter, 2006).