Des Moines Public Schools (DMPS) implemented READ 180 with sixth- through eleventh-grade students with disabilities. Policy Studies Associates (PSA) analyzed five years of data on more than 1,200 READ 180 participants, as provided by DMPS (Hewes, Palmer, Haslam, & Mielke, 2006). For the purposes of this analysis, students with disabilities who were no longer enrolled in READ 180 served as the comparison group.
Across the five years covered in this study, the annual number of students who enrolled in READ 180 for the first time ranged from just under 200 to almost 350. Cohort 1, which included students whose first enrollment was in 2000–2001, was the largest READ 180 cohort, enrolling 110 sixth graders, 130 seventh graders, and 102 eighth graders—a roughly even distribution across the middle school grades that were the initial focus of READ 180 in DMPS. Subsequent cohorts enrolled similar numbers of sixth graders, but most seventh and eighth graders in subsequent years were students continuing from previous cohorts, with fewer seventh and eighth graders identified for first-time enrollment. Thus Cohorts 2 through 5 are somewhat smaller than the first cohort, with Cohort 4 the smallest of all of the cohorts. All five of the cohorts were pooled into a single, large sample of students for this analysis.
In order to measure the effectiveness of READ 180, pretest and posttest Stanford Diagnostic Reading Comprehension Subtest, Version 4 (SDRT-4 Comprehension) and Reading Inventory® data were collected. Growth curve modeling analysis revealed that, on average, READ 180 middle and high school students achieved a 21 scale score point gain on SDRT-4 Comprehension each year, compared to the 15 scale score point gain among non-READ 180 students. These gains translated into 1.43 years of growth for READ 180 students and 1.02 years of growth for non-READ 180 students (Graph 1).
Further, the analysis revealed that for every additional year that students with disabilities participated in READ 180, scores on the SDRT-4 Comprehension Subtest increased by approximately six scale score points above and beyond the expected yearly growth in achievement. This increase is equivalent to 0.4 years of growth above and beyond the expected annual growth. As Graph 2 shows, after three years, the gap widened to 12 scale score points between the three-year READ 180 students versus the one-year READ 180 students, 658 versus 646. This is the equivalent of a difference of four-fifths of a year of growth. This pattern held for the other grade levels on SDRT-4 Comprehension, with an average 12 scale score point advantage for students who continued in READ 180.
Each additional year of READ 180 was also associated with an annual improvement of approximately 30 Lexile® measures on the Reading Inventory. This statistically significant increase can be translated into 0.26 years of growth above and beyond the expected annual growth.
Hewes, G. M., Palmer, N., Haslam, M. B., & Mielke, M. B. (2006). Five years of READ 180 in Des Moines: Improving literacy among middle school and high school special education students. Washington, DC: Policy Studies Associates, Inc.