Using the Certainty Response Index to Screen for Possible Misconceptions in Year Two 2D and 3D Shape Learning

Abstract

Correctness alone does not distinguish an uncertain geometry response from a confidently held error. This descriptive pilot examined the Certainty Response Index (CRI) in 2D and 3D shape learning among 30 purposively selected Year Two students at one Malaysian primary school. The 10-item instrument paired an answer with a confidence rating on a five-point scale; ratings of 1–3 were classified as low and 4–5 as high. Data collection extended over one month through one-hour sessions held twice weekly. The student-level summary classified 10 students (33.3%) as correct-high confidence, 6 (20.0%) as correct-low confidence, 6 (20.0%) as incorrect-low confidence, and 8 (26.7%) as incorrect-high confidence. These aggregate profiles support differentiated follow-up assessment, but they do not establish item-level misconception prevalence or diagnostic accuracy. Formal instrument validation, test–retest reliability assessment, and independent corroboration of possible misconceptions were not conducted. The rule for deriving one profile per student from multiple items is also unspecified. High-confidence incorrect profiles are therefore treated as screening flags requiring reasoning evidence. Within these limits, CRI can organise further assessment of early shape learning; it cannot independently confirm the conceptual source of an error.