This ex post facto, quasi-experimental, quantitative research examined the effectiveness of a weekly progress monitoring program—as multi-tiered support—with sixth through eighth graders who require special education in middle school. Through a pretest-posttest, nonequivalent control group design, the study compared reading improvement on the Jerry Johns Basic Reading Inventory (BRI) and a high-stakes state accountability assessment (MAP-CA) over a four-year period. Additionally, correlation between the BRI and AIMSweb Reading Curriculum-Based Measurement (R-CBM) was computed. According to the BRI, results indicated a significant increase in the reading achievement for students in the treatment group. Notably, no significant difference in scaled scores on the MAP-CA occurred. Calculations defined a strong positive correlation (r=.772) between Lexile scores on the BRI and R-CBM. Limitations that impacted the findings included experimental control over specific reading interventions implemented and teacher styles, tenure, qualifications, and expertise. Furthermore, missing MAP-CA data for eighth-grade students affected results due to the replacement of MAP-CA with end-of-course (EOC) exams in ninth grade. An analysis of complete MAP-CA data for sixth-grade students revealed faster gains in reading for the treatment group. Implications for policy and practice suggest increased use of progress monitoring in middle schools, need for high-quality professional development of educators, importance of data coaching, and continued administration of the BRI in conjunction with R-CBM as formative and summative tools to evaluate reading goals on Individualized Education Programs.