Development of Diagnostic Items and Exploration of Adaptive Learning Applications: Focusing on the Concept of Additive Color Mixing

Purpose: This study aimed to analyze elementary school students’ understanding of the concept of additive color mixing, develop assessment items to diagnose their conceptual understanding, and explore the potential application of these items in adaptive learning environments. Methods: A survey was conducted with 565 sixth-grade students who had no prior learning experience related to the topic. Based on expert review, the alternative concepts were categorized into specific types. Subsequently, diagnostic and formative assessment items were developed, and their content validity was verified using CVR (Content Validity Ratio) and CVI (Content Validity Index) indicators. Results: Students exhibited various alternative concepts, such as confusing additive RGB light mixing with pigment mixing and interpreting light intensity as color darkness. Based on these findings, three diagnostic and four formative assessment items were developed, all of which were validated for content accuracy. Conclusion: The developed items were designed to precisely diagnose various types of student conceptions and can serve as foundational tools for supporting personalized feedback and instructional design when applied to AI-based adaptive learning systems in the future.