Developing Mathematical Reasoning Skills on CER Framework of Grade 8 Students in Opportunity Expansion Schools through Mathematical Argumentation Activities on the Pythagorean Theorem

Abstract

This study is action research aimed to 1) investigating approaches to developing mathematical reasoning skills on CER framework through mathematical argumentation-based learning activities, and
2) enhancing the mathematical reasoning skills on CER framework of Grade 8 students on the topic of
the Pythagorean Theorem. The participants consisted of 9 students from a small-sized opportunity expansion school. The research instruments included 1) 4 lesson plans, with one lesson plan implemented in each action research cycle, totaling 4 action research cycles 2) reflective journals on learning activity implementation 3) activity worksheets, and 4) an assessment of mathematical reasoning skills based on
the Claim–Evidence–Reasoning (CER) framework. Qualitative data were analyzed through content analysis of students’ worksheets and the mathematical reasoning assessment based on the CER framework, while descriptive statistics were used to analyze quantitative data. The findings of this research were as follows
1. The learning management approach for developing mathematical reasoning skills based on the CER framework through mathematical argumentation highlights important roles of both teachers and students. Key emphases include 1) teachers selecting open-ended problem situations or situations with multiple possible solutions, using language that students could easily understand before gradually extending to more complex problems. 2) teachers preparing students with the prerequisite knowledge and mathematical content necessary for mathematical reasoning. Consequently, foundational content was introduced during Action Cycles 1–2, while the concepts of the Pythagorean Theorem and its converse were emphasized in Action Cycles 3–4. and 3) teachers encouraging students to engage in analytical thinking, leading to
the presentation and refinement of claims relevant to the given situations, supported by appropriate reasoning, while enabling students to organize their mathematical thinking systematically and logically.
2. The results of the development of mathematical reasoning skills, based on the CER framework assessment, indicated that students achieved Level 3 in Claim (C), Level 3 in Evidence (E), and Level 2 in Reasoning (R). Overall, students’ mathematical reasoning skills in all CER components improved and reached Level 3. These findings demonstrate that the learning management approach implemented in the context of an opportunity expansion school was effective in developing students’ mathematical reasoning skills.