“…In accordance with the main concept in Vygotsky's learning theory (Shabani, 2016;Shabani, Khatib, & Ebadi, 2010), Zone of Proximal Development (ZPD), there are various difficulties students may experience towards their potential zones, including 1) when solving problems students have limited working memory; 2) students' difficulties in carrying out analysis in solving problems; 3) the initial knowledge possessed by students is not comprehensive and is not well integrated into the subject matter; 4) students' difficulties in recalling knowledge that has long been obtained. According to van de Pol, Volman, and Beishuizen, (2010) and van de Pol, Volman, Oort, and Beishuizen (2015), various difficulties will be reduced by using the application of scaffolding in the learning process. This is in accordance with the results of the study that through the learning process with the CPS model accompanied by scaffolding higher learning outcomes were obtained.…”