Nationwide, middle school students are transitioning to high school without being able to read at grade level. This occurs despite schools adopting Response to Intervention systems to provide additional reading instruction to those who are reading below grade-level. This study examined students' posttest reading comprehension scores to determine if the reading interventions in place in a Title 1 school in a rural, Midwest district were statistically significant when compared to the posttest scores of below grade-level readers who were not enrolled in a reading intervention. The study used a quantitative approach with a quasi-experimental design. An Analysis of Covariance (ANCOVA) was used to compare posttest scores while controlling for students' initial reading level. The participants in this study included 173 sixth, seventh, and eighth grade students identified as reading below grade-level. There were total of 79 sixth grade students. Of those, 19 received reading intervention using the READ 180 curriculum; 19 received reading intervention class using a teacher-generated curriculum, and 41 received no intervention. In total, there were 94 seventh and eighth grade students. Of those, 33 received a reading intervention class using the READ 180 curriculum, 45 received a reading intervention class using a teacher-generated curriculum, and 16 had no reading intervention. The results of this study show that there were statistically significant differences between sixth grade students enrolled in READ 180 when compared to students not in a reading intervention class. The non-intervention group outperformed the READ 180 group. The posttest scores did not differ for sixth grade students in an intervention class using READ 180 and an intervention class not using READ 180. In the seventh and eighth grade group, there was no statistically significant difference in the posttest scores between the intervention groups and no intervention group. These findings highlight the complexity of increasing the reading comprehension of below grade-level readers in middle school. [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.]