Development and differences in creative thinking-based ethnomathematics: a cross-sectional study in secondary education

Context and relevance. Creative thinking (CT) in mathematics is essential for academic success and is a key component of 21st-century competencies. While there is increasing interest in integrating ethnomathematics with mathematical creative thinking (MCT), research remains limited, particularly in developing and differentiating test items, as well as exploring both test validity and students' abilities. Objective. This study aimed to assess of the Mathematical Creative Thinking-Based Ethnomathematics (MCTBE) test in evaluating CT skills among Indonesian students in Grades 7, 8, and 9. Hypothesis. (1) The reliability and validity of data fit in MCTBE can be effectively assessed and improved using Rasch models. (2) Certain test items in MCTBE exhibit differential item functioning (DIF) based on gender. (3) MCTBE scores significantly differ by gender and grade level among secondary school students. (4) Specific aspects of MCTBE show significant differences between male and female students across different grade levels. Methods and materials. This cross-sectional study was analyzed using the Rasch model. The developed instrument consisted of 20 test items, including both figural and verbal components, based on MCT-ethnomathematics. These items assessed fluency, flexibility, originality, and elaboration. Results. The study found that the MCTBE test, which included four tasks, was both valid and reliable according to Rasch analysis. The results indicated that male students outperformed female students, with Grade 9 students achieving the highest scores. While minor differences were observed in fluency and flexibility, no significant differences were found in elaboration and originality. Conclusions. The study confirmed the validity and reliability of the MCTBE test and highlighted the importance of assessing students' MCT abilities. These findings are useful for teachers, government, and researchers to enhance mathematics education quality and ensure accurate assessment of students' mathematical abilities.