Tufan, MehtapYildirim, SonerAltunay, BanuInformation Systems Engineering2025-09-052025-09-0520251475-939X1747-513910.1080/1475939X.2025.25318682-s2.0-105012427306https://doi.org/10.1080/1475939X.2025.2531868https://hdl.handle.net/20.500.14411/10769This study aimed to develop and evaluate a technology-based instructional tool using the Direct Instruction Model (DIM) for teaching geometric concepts - cube, cylinder and cone - to students with mild intellectual disabilities (ID). The 'Shape Finder' application was designed following DIM principles and assessed using a multiple probe design across participants. Four students with mild ID, their three teachers and six special education experts participated. Data collection involved app-based performance metrics, observations and interviews. Results indicated that the Shape Finder effectively supported students' acquisition, retention (up to five weeks), and generalisation of the targeted geometric shapes to real-world objects. Interviews confirmed the application's social validity. The findings highlight that integrating evidence-based instructional models with technology can enhance concept learning for students with mild ID, facilitating both short-term gains and long-term retention. This study underscores the potential of well-designed digital tools in special education to support conceptual understanding and generalisation across contexts.eninfo:eu-repo/semantics/closedAccessSpecial EducationApplications In Subject AreasDirect Instruction ModelConcept AcquisitionTechnology Integration In Special EducationArticle