The Effect of Inclusion on Student Performance on State Assessments

Years of research on the effect of inclusive placements on the academic performance of students with disabilities has been notable for its inconsistent and contradictory findings. This study examined the performance of 651 elementary, middle, and high school students with disabilities in a large urban school district in a plains state on state assessments in reading and mathematics. The goal of this analysis was to determine the extent to which the inclusion of students with disabilities in general education classrooms impacts their performance on state assessments. Scores of students taking the general assessment and the modified assessment were included in this study. The dependent variable was each student's reading and mathematics score on the state assessment, and the independent variable was the student's access to general education curriculum as measured by Office of Special Education Programs (OSEP) inclusiveness designations. Control variables were selected to test for the effects the individual variables of a student's disability type, race, gender, and socio-economic status, and because students in the data were nested within schools, hierarchical-linear analysis was employed to reduce potential biases due to correlated observations. Finally, the regression models included school-level predictors for building inclusiveness, qualifications of general and special education teachers, and proportions of students with disabilities, students from low-income families, and students of color. The study produced four main findings. First, the student-level variable, OSEP level of inclusion, was a highly significant predictor of increased academic performance on state assessments in both reading and mathematics in every model. Second, the student-level predictor, free/reduced lunch, had a highly significant negative effect on student performance in reading and in mathematics, nearly twice the positive effects of inclusion. Third, the school-level predictor, percent of minority student enrollment of school, had significant negative effect on student performance in mathematics. Finally, the interaction of student OSEP level of inclusion and the school's percent of highly qualified special education teachers had a significant positive effect in mathematics, suggesting that the effect of inclusiveness is amplified by access to a highly qualified teacher in this subject. In terms of the primary question of the effect of inclusive placements on the academic performance of students with disabilities, results indicate that as the student's level of inclusion increases, performance on state assessments improves in both reading and mathematics.