This study aimed to explore high school biology teachers’ epistemological criteria and their attention to reasoning and argumentation within their instructional practices. This study investigated: (1).what epistemological criteria do high school biology teachers use when justifying the validity of conclusions, (2) what is the frequency of the explicit use of reasoning and argumentation, if any, in high school biology teachers’ instructional practices, and to what extend are reasoning and argumentation skills reflected, if at all, in high school biology teachers’ modes of assessment.
Three different data collection methods were employed in this study; face-to-face interviews, classroom observations, and document collections. This investigation was made by having teachers provide an argument about the validity of hypothetical conclusions drawn by the students based on two different scenarios related to evolution. Toulmin’s Argument Pattern used to create rubric to analyze high school biology teachers’ levels of reasoning through argumentation.
Results of the data analysis suggested following findings. First, high school biology teachers participated in this study presented variety of epistemological criteria which were presented as high, moderate and low levels of reasoning through the argumentations. Second, elements of Toulmin’s Argument Pattern were visible in the participants teaching practices, however students were not explicitly introduced to a well structured argument in those classrooms. Third, Interview Protocols designed for this study were found useful to identify the epistemological criteria and level of reasoning through argumentation.
Results of this study suggest the following implications for improving science education. Toulmin’s Argument Model should be introduced to teachers through teacher education or professional development programs to increase the use of reasoning and argumentation in instructional practices. The results suggest that use of Toulmin’s Argument Pattern to evaluate high school biology teachers’ presented levels of reasoning is a promising approach to understanding the structure of reasoning and argumentation that biology teachers use when providing judgments about the validity of hypothetical conclusions. The interview protocols and the rubrics used in this study should be tested in different subject areas in order to enhance and validate the use of Toulmin’s Argument Pattern in measuring individuals’ epistemological criteria and level of reasoning.