“…Another subset of studies explicates the features of talk that render it collaborative and thus more productive in terms of learning and equity. These studies often refer to 'exploratory talk', a particularly productive subtype of group talk marked by: 1) co-construction of ideas (e.g., Howe, 2009;Rafal, 1996;Storch, 2001); 2) constructive disagreement (e.g., Barnes, 1976;Connolly & Smith, 2002;Cook-Gumperz & Szymanski, 2001;Corden, 2001); and 3) negotiation of ideas (e.g., Brice, 2002;Long & Porter, 1985;Mercer, 1996). A related thread of research has focused on teachers' role in shaping group talk via scaffolding (Gillies & Kahn, 2009;Kramer-Dahl, Teo, & Chia, 2007;Sharpe, 2008;Webb et al, 2009), explicit instruction (Christie, Tolmie, Thurston, Howe, & Topping, 2009;Gillies, 2010;Mercer, Dawes, Wegerif, & Sams, 2004;Szymanski, 2003), and fostering social support amongst peers (Blatchford, Kutnick, Baines, & Galton, 2003;Dale, 1994;Edwards, 2005).…”