“…This study's instruction was designed online in the consideration that educational technologies supported, argumentation-based instructional applications. The studies showed that argumentation-based instructional applications have been increasing in Finland (Kiili, 2013), Norway (Ludvingsen, 2012), Australia (Butchart, Forster, Gold, Bigelow, Korb, Oppy & Serrenti, 2009;Davies, 2009), United States of America (Hoffman, 2008) and United Kingdom (Okada, 2008) in recent years and such applications had positive impacts on the development of students' cognitive, affective and psychomotor skills. Teachers are needed to be informed of how to evaluate mathematical arguments, to determine the accuracy of mathematical propositions and to prove the accuracy of mathematical arguments which they think of as accurate.…”