The effect of critical thinking education on secondary students' critical thinking skills and attitudes to the Turkish course

In the research, it is aimed to determine the effect of content-based critical thinking teaching on students' critical thinking skills and their attitudes towards Turkish lesson. For this purpose, explanatory sequential design was used in the research. Due to the nature of the explanatory sequential design, a quantitative research approach was adopted in the first stage and a qualitative research approach in the second stage. In the first stage of collecting quantitative data, quasi-experimental design with pretest-posttest control group was preferred as a model, and phenomenology design was preferred for qualitative data. In the quantitative data collection process of the research, 50 students, 25 in the experimental group and 25 in the control group, who were studying in the 5th grade of Muş Şeker Secondary School, were determined by criterion sampling method. In the qualitative data collection process, 12 students who were determined by the maximum diversity sampling method, one of the purposive sampling methods, were included. "Critical Thinking Achievement Test", "Attitude Scale Towards Turkish Lesson" and "Semi-Structured Interview Form" were used to collect data in the research. The quantitative data of the study were analysed with parametric tests. Qualitative data of the research were analysed by content analysis. In the study, it was determined that there was a significant difference between the critical thinking skills of the students before the content-based critical thinking skills training and the critical thinking skills of the students after the content-based critical thinking skills training. The significant difference identified was evaluated as content-based critical thinking skills trainings were effective on students' critical thinking skills. In the study, it was determined that the content-based critical thinking skills curriculum affected students' critical thinking levels positively in many ways. These are listed as the ability to make decisions, to think differently, to comprehend the plot of the events, to distinguish the cause-effect relationship in the events, to explore and to make evaluations based on what they have discovered, and to experience positive changes in their ability to reach a conclusion. Keywords: Critical Thinking, Critical Thinking Teaching, Content-Based Critical Thinking Teaching, Critical Thinking Skills, Attitude Towards Turkish Lesson.