Inklusiver Mathematikunterricht in der Sekundarstufe: Eine Pilotstudie zur Prozentrechnung

In order to deal with students’ heterogeneity, inclusive subject matter instruction requires a combination of approaches from special needs education and subject matter didactics. However, there are hardly any empirically tested instructional approaches, especially for secondary schools. This pilot study investigated an inclusive teaching unit for percentages designed according to four design principles: focus on conceptual understanding on different levels, connecting multiple representations, language-responsiveness and assuring accessibility. The effectiveness of the teaching unit for all students was investigated in a control-group pretest posttest design with 259 seventh graders. We used hierarchical linear regression models to study the treatment effect. The analysis reveals that the mathematical basic competencies are the best predictor for students’ post test score in conceptual understanding of percentages whereas the treatment factor is the second-best predictor. The intervention group (n = 169) achieved significantly higher scores in the post test than the control group (n = 90) which participated in conventional instruction with their regular textbook. This finding indicates the efficacy of the teaching approach. Future studies should focus on general and differential effects for overcoming the current methodological limitations.