The purpose of this non-experimental casual comparative study was to examine the relationship between the educational environment (i.e., co-taught, or resource room), and academic growth with oral reading fluency (ORF) measures for second and third grade students with disabilities. The study also explored possible unique predictors of increased ORF for second and third grade students with disabilities. The data indicate that the educational environment or service delivery model had the most significant effect on students' ORF scores (t = -6.03, p = 0.000). Students' gender, type of disability, and the level of support received were not significant predictors of their ORF scores at the end of the school year. Students who participated in co-taught classrooms scored 12.05 points higher on ORF at the end of the school year than students in resource classrooms ( B = -12.05, p = 0.000). These results support the least restrictive environment (LRE) mandate under IDEA (2004) and provide educational leaders more quantitative data to support the educational placement decisions for students with disabilities during IEP team meetings. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]