Despite decades of advocacy, most students with developmental disabilities continue to spend the majority of the school day in self-contained special education classrooms. However, there is tremendous variability of educational placement across the United States. Identification of geographic trends that explain this variability could provide…

Thirty-five studies on the efficacy of special class versus regular class placement for mildly handicapped students were reviewed for the power of their statistical tests. Twenty-one studies had adequate power to detect a large effect size but the power to detect a medium effect size was no better than chance. (Author/DB)