An Initial Investigation of the Implementation, Effects, and Social Validity of a Mathematics Vocabulary Intervention

Abstract This study examines the implementation, effects, and social validity of an explicit systematic mathematics vocabulary (MV) intervention for students with learning disabilities or difficulties. Participants included 30 students ages 11–14 who demonstrated a lack of mastery of third-grade MV and were assigned to treatment or control groups within classes. The two groups were similar at pretest in mathematics achievement and MV; however, the treatment group ( M = 42.6, adjusted M = 42.4) significantly outperformed the control group ( M = 34.1, adjusted M = 34.3) on the MV posttest ( b = 8.15, p < .001, 95% CI [5.30, 11.01], g = 1.99, adjusted g = 1.80). Observational data show teachers implemented the intervention with acceptable levels of fidelity. Social validity data suggest teachers found the intervention acceptable and easy to use. Results of this study suggest well-designed explicit, systematic instruction can produce positive effects when teaching MV to students requiring intensive MV intervention.