Using CRA-I to Teach Fraction and Decimal Concepts to Students With Learning Disabilities.

This article examines the effects of the concrete-representational-abstract–integrated (CRA-I) instructional sequence on the fraction and decimal learning outcomes of three elementary students with learning disabilities. Using a single-case multiple probe design, the study found that CRA-I instruction, which systematically combines and fades concrete materials (e.g., fraction blocks, coins), representational tools (e.g., number lines, pictures), and abstract symbols, led to decreased errors in fraction magnitude estimation, improved accuracy in adding fractions with unlike denominators, and enhanced ability to write fractions as decimals. The intervention was delivered over 15 lessons in a special education resource setting, and all students demonstrated significant gains across the targeted skills, with treatment fidelity and interobserver agreement exceeding 99%. While the study supports CRA-I as a promising approach for teaching rational number concepts to students with learning disabilities, it notes limitations including the small sample size, researcher-led implementation, and lack of maintenance data, suggesting further research is needed to establish CRA-I as an evidence-based practice.