Exploring high school students’ perspectives on mathematical argumentation in geometry learning

This study employed an exploratory quantitative survey design to investigate high school students’ self-reported perceptions of mathematical argumentation in geometry learning. A 15-item questionnaire was developed on a five-point Likert scale with reference to Toulmin’s argumentation model, used as a conceptual background; 11 items were retained following exploratory factor analysis. Data were collected through in-person administration from 437 high school students in An Giang Province and Can Tho City, Vietnam, using convenience sampling, and analysed in Jamovi (version 2.6.16.0). Exploratory factor analysis yielded a four-factor solution accounting for 61.3% of total variance: Participation in Mathematical Argumentation (PMA), Use of Reasoning Components (URC), Perceived Importance of Mathematical Reasoning (PIMR), and Difficulties in Geometric Reasoning (DGR). An exploratory discrepancy was observed between students’ reported valuing of argumentation (PIMR M = 4.18) and their reported participation (PMA M = 2.88); because these factors derive from different item sets, this pattern is interpreted cautiously rather than as an established attitude–behaviour gap. Group comparisons revealed significant differences by gender (PMA, DGR), by enrichment course participation (PIMR, PMA, DGR), and across all four factors by mathematics achievement level. A counterintuitive finding was that higher-achieving students reported greater difficulties in geometric reasoning than lower-achieving peers, reported here as an exploratory observation warranting further investigation. The findings suggest that fostering argumentation in geometry classrooms may benefit from approaches that address students’ motivational barriers, expand participatory opportunities, and develop component reasoning skills. Limitations of the study and directions for future research are discussed.