“…The former, which make up the bulk of these papers (see for example the reviews by De Wever, Schellens, Valcke, & Van Keer, 2006;Dennen, 2008;Donnelly & Gardner, 2009), argue that ontopic talk makes a direct contribution to the processes involved in learning (e.g. Guzdial & Turns, 2000;Lipponen, Rahikainen, Lallimo, & Hakkarainen, 2003;Veerman & Veldhuis-Diermanse, 2001). This approach is shared by a great many other works which, while not explicitly identifying on-topic talk as their focus, use a number of analysis categories -elaborating and summarizing ideas or concepts, developing and exploring hypotheses, proposing new coconstructions on topics, defining terms and judging definitions, refining or elaborating already stated information, analysing arguments and applying new knowledge -which clearly correspond to this type of talk (see for example De Wever, van Winckle, & Valcke, 2008;Gunawardena, Lowe, & Anderson, 1997;Weinberger & Fischer, 2006;Zhu, 2006).…”