The purpose of this study is to investigate the effect of teaching 9th grade Functions subject through argumentation on students' science process skills, attitudes towards Maths, willingness for argumentation and conceptual comprehension. The study was designed as a quasi-experimental model with pretest-posttest control group. It was carried out with 60 students totally at two different 9th classes of a Science High School in a city located in the Eastern Anatolian Region during fall semester of 2014-2015 educational years. One of these two classes was selected as the experiment group (20 female-10 male) and the other one was selected as the control group (17 female-13 male) randomly before the practice. The study was implemented in "Functions" unit. Considering the results, it was concluded that argumentation method had a positive effect on science process skills of the experiment and control group students and AWS implemented only to control group increased the argumentation willingness of the students and the conceptual comprehension frequency of experiment group students were more than the control group students.