Teaching Conceptual Subitizing Using Ten-Frame Representations to Students with Intellectual Disabilities

Conceptual subitizing is a foundational early numeracy skill that supports broader mathematical learning in children. However, few studies have explored systematic instructional approaches for teaching this skill to students with intellectual disabilities. The present study examined the effectiveness of an iPad-supported simultaneous prompting (SP) procedure to teach conceptual subitizing using ten-frame representations. Four participants with intellectual disabilities, aged 12–15 years, participated in a single-subject multiple-probe design across participants. Dot quantities ranging from 1 to 10 were presented on an iPad within ten-frame representations for 250 ms. The study also explored students’ performance in determining total quantities using ten-frame representations. In this task, first-attempt accuracy and completion time were measured before and after the conceptual subitizing intervention. Visual analyses indicated that the SP procedure was effective, and three participants achieved mastery in conceptual subitizing. Students generalised conceptual subitizing skills to different materials and maintained these skills for several weeks. In the total quantity task, completion time decreased for all participants. First-attempt accuracy improved for three participants and remained unchanged for one participant. However, the pre- and post-intervention assessments differed in presentation and instructional guidance. Therefore, the results are not directly comparable, and the observed changes cannot be attributed solely to the conceptual subitizing intervention. Teachers reported positive views about the SP procedure. The findings suggest that an iPad-supported SP procedure with ten-frame representations can support the development of conceptual subitizing in students with intellectual disabilities.