“…Of these, 220 articles included three or more comment strings. To investigate whether and how young people actually engaged in substantive debate about the focal topic -a goal for users when designing the app -these comment strings were coded for evidence of argumentation about environmental issues (Greenhow, Menzer, and Gibbins 2015); extending an argumentation coding system originally designed for 'formal' computer-supported collaborative learning environments (Sadler, Barab, and Scott 2006;Weinberger and Fischer 2006), comments strings were coded for four argumentation dimensions: participation, epistemic, argument, and social co-construction skills. Results indicated that these three skill subsets were also evident in the Hot Dish environment at relatively high rates.…”