Abstract
The first author, a part-time lecturer teaching mathematics at a high school, noticed discrepancies in students’ understanding of the connections between units and topics during instruction. To examine students’ cognitive structures regarding the teaching materials, a questionnaire and a test based on rubrics were administered, and the data were analyzed using fuzzy theory. As a result, it became possible to visually identify the units that students mistakenly believe they understand, as well as the differences between the inter-topic connections assumed by teachers and those perceived by students.
