Are Effective Teachers for Students with Disabilities Effective Teachers for All?
Students with disabilities make up approximately 14% of the K-12 student population, and over 60 percent of these students spend 80% or more of their time in school in the general education classroom setting. While the intention behind mainstreaming is to enable students with disabilities (SWDs) to learn in the least restrictive environment, it is nonetheless important to understand the quality of education they receive in these environments. In particular, general education teachers (GETs) typically enter the field with limited preparation to work with students with disabilities. Only seven states require all teachers to complete coursework for working with SWDs, and only two require clinical experiences working with these students. Thus, general education teachers are likely to receive minimal coverage of special education teaching methods in their coursework and have few practice opportunities focused on SWDs.
Despite this lack of training, nearly all teachers will work directly with SWDs, and some teachers may be better or worse equipped to meet these students’ needs. Yet little is known about the effectiveness of GETs with this sub-population of students, and some GETs may be more or less successful at working with SWDs.
That some teachers may vary in effectiveness with different groups of students is not a new concept. Loeb, Soland, & Fox (2014) have documented that teachers are differentially effective at improving academic outcomes for English Learners. To date, no such studies have been conducted with SWDs. However, there is considerable evidence that SWDs benefit from specific kinds of instruction. Within general education classrooms, effective practices for instructing SWDs include intensive instruction that focuses on fewer and higher priority skills and concepts. If teachers in general education classrooms are not prepared to implement these techniques, then SWDs may not receive the quality education they deserve.
To test the relative effectiveness of GETs with SWDs, we leverage Los Angeles Unified School District (LAUSD) administrative data from SY 2007-2008 through SY 2017-2018 and disaggregate overall measures of teacher effectiveness into measures focusing specifically on SWDs and non-SWDs. Specifically, we generate two different sets of value-added measures (VAMs) for each teacher (n = 6,200): a SWD VAM and a non-SWD VAM. Using these two measures, we explore the following research questions:
Do some teachers have a relative advantage in teaching SWD versus non-SWD students? Are SWDs sorted to teachers with higher/lower SWD VAMs? Are there differences in teacher outcomes (evaluation scores, hiring scores, attendance) for teachers who exhibit a relative advantage in teaching SWDs over non-SWDs? Do SWDs who are assigned to relatively effective middle school teachers tend to have better high school outcomes? We define a relative advantage in teaching SWDs as a teacher falling into a higher place in the distribution of SWD VAM scores than where the teacher falls in the distribution of non-SWD VAM scores. Placing SWDs in classrooms where teachers exhibit a relative advantage at instructing SWDs can potentially raise the test scores of these students more efficiently. Using this definition, we examine whether some teachers are more effective at teaching SWDs and whether this is consistent across test and non-test score outcomes. Specifically, we explore relationships between teacher quality as measured by value-added, students’ disability status, and outcomes such as test scores, attendance, and course-taking. For medium-term outcomes, we are also able to observe students in high school and evaluate their course taking, grades, and meeting local university minimum requirements. We also assess the allocation of SWDs and GENs to teachers who are more/less effective at educating them, and whether accessing a teacher who is more effective at teaching SWDs helps SWDs achieve important outcomes.
We find that a sizeable amount of the top performing teachers for non-SWDs are not necessarily the most effective teachers for SWDs (as measured by VAMs). This result holds across both math and ELA courses. Students with disabilities also have a higher (lower) probability of being taught by teachers within the lowest (highest) quintile of SWD and non-SWD VAMs within schools. These preliminary results suggest that teachers may need additional training to become successful helping SWDs to learn. Moreover, these findings raise concerns about the equitable distribution of high-quality teachers to students with disabilities, suggesting that school and district leaders may need to proactively consider the placement of SWDs with teachers who are more adept at teaching this critical population of students.