INVESTIGATION OF THE EFFECTIVENESS OF USING SELFDETERMINATION THEORY IN TEACHING SCIENCE FOR GRADE EIGHT STUDENTS: A CASE STUDY IN SRI LANKA

Science is highly important as it focusses on enhancing the quality of human life. Though, science is perceived to be an interesting discipline, students' performance in the field of school science is not very satisfactory. Self-determination theory (SDT) assumes that inherent in human nature is the propensity to be curious about one's environment and interested in learning and developing one's knowledge. Thus, SDT can be used to teach science effectively in classrooms to enhance students' performance. As described in SDT, people have three innate psychological needs; competence, autonomy and relatedness. If these needs are fulfilled, the optimal functioning of human beings can be obtained. Hence, this study focused in investigating the effectiveness of using SDT in teaching “Main Biological Processes in Plants” for Grade 8 students. The study was conducted using two groups of students as the experimental and the control. The experimental group was instructed using SDT while the control group was taught using traditional method. The students' performance, psychological relatedness, competence, and the autonomy showed higher in the experimental group compared to the control group. Thus, the results indicate that the instructional approach based on SDT is very effective compared to traditional approach of instruction in teaching science as SDT approach develops intrinsic motivation of students.