Special education: Beneficial to many, harmful to others

Over the past 45 years, there has been a dramatic increase in the fraction of students receiving special education (SE) services in public schools. Currently, over 13% of U.S. public school students participate in SE programs annually, at a cost of $40 billion.

Despite the rising cost of, and participation in, SE, there is limited quantitative evidence on who benefits from SE and to what extent SE impacts achievement in school and beyond. On the one hand, SE students likely benefit from the individualized educational support that SE offers. On the other hand, for students with less severe conditions, there are reasons why SE participation could be harmful: Being placed in segregated learning environments or held to relatively lower expectations regarding achievement may inhibit long-run success. Though the purpose of SE is to ameliorate the challenges that students with disabilities face throughout schooling and later in life, exactly which students benefit from SE participation is less clear.

For students of color in particular, education experts differ on whether SE participation is beneficial. Black students are about one and a half times more likely to receive SE services in public school than white students. This has sparked discussion of whether these differences in SE classification between white and Black students imply that some Black students are misplaced in SE (e.g., due to racial bias from administrators or placement rubrics). And yet, after conditioning on important background characteristics such as prior academic achievement and socioeconomic status, Black students are less likely to receive SE services relative to their white peers. These findings have led to concern about whether Black students should be placed in SE more often, despite appearing to be overrepresented in SE.

Improving our understanding of the impacts of SE placement overall and for students of color is critical to informing policy. However, since changes in SE placement are driven by student need, it is difficult to determine what experiences a student would have in the absence of SE services. In two recent studies, we identify the impacts of SE by studying the effects of a Texas policy that capped district-level SE enrollment and disproportionality for Black and Hispanic students (defined as the difference in the share of Black or Hispanic students in SE and the overall share in a district). Our results suggest appropriate SE classification is key. When students of any race are removed from SE in response to the cap on overall SE enrollment, their long-run outcomes suffer. However, when Black students are removed from SE in response to capping disproportionality, their outcomes improve. While uncovering mechanisms is difficult given data constraints, our results suggest that these differences may be driven by whether students were appropriately identified for SE.

What Happened in Texas?

In 2005, the Texas Department of Education implemented a policy that rated districts on their SE enrollment rates and disproportionality rates. The policy stated that districts were only in compliance with state standards if their SE enrollment rate was 8.5% or less and their disproportionality rates for Black and Hispanic students were 1% or less. As illustrated in Figure 1, over the next 10 years statewide SE enrollment declined by 3.5 percentage points, from about 12% to 8.5%. By 2018, roughly 225,000 fewer students were enrolled in SE programs annually across the state.

These thresholds led to a large and sudden drop in SE participation. In 2016, more than 10 years after the policy was implemented, an investigative article in The Houston Chronicle alerted the public to the existence of the SE enrollment cap, sparking significant public outcry and debate. Subsequently, the federal government conducted its own investigation and, in 2018, it determined that the 8.5% district SE enrollment target violated federal disability law. (The disproportionality caps, however, were not deemed illegal, and states are encouraged to closely monitor race-based differences in SE enrollments.) The 8.5% enrollment cap, while legally problematic, provides a unique opportunity to learn about who benefits from SE services.

How Did This Impact Students?

In our two studies, we compare outcomes across districts over time to investigate the impacts of limiting SE access on students’ long-run success. Our framework allows us to utilize differences in how intensely districts are affected by the two different policy thresholds by comparing districts above each threshold to those below the same threshold before and after the policy went into effect. In other words, some districts felt more pressure to reduce overall SE enrollments, while others felt more pressure to reduce Black disproportionality (and in practice, we found a low correlation between district-level SE rates and Black disproportionality rates). It is this implied policy pressure that we use to create our estimates.

There are three main takeaways from this work:

1. First, educational attainment among SE students significantly declined in districts pressed to reduce overall SE enrollment. We find that, for students already in SE before the policy went into effect, the likelihood of SE removal increased by 13% as a result of capping overall SE enrollment. These reductions in SE access generated significant declines in educational attainment for previously classified SE students, who were 2.7% less likely to complete high school and 3.6% less likely to enroll in college. Lower-income students experienced even larger decreases in high school completion and college enrollment. These declines in educational attainment as a consequence of SE removal can likely be explained by reductions in the additional resources aimed at boosting student learning (such as one-on-one or small-group instruction) and other accommodations (such as exemptions from high school graduation requirements).
2. Second, Black SE students’ educational attainment improved in districts pressed to reduce Black disproportionality. For Black students who were in SE before the policy went into effect, we find that the likelihood of SE removal increased by 5.5% as a result of capping Black disproportionality and 15% as a result of capping overall SE enrollment. Interestingly, losing SE due to the cap on disproportionality had opposite impacts on long-run outcomes as losing SE due to the cap on overall enrollment. For Black SE students more intensely affected by the SE enrollment cap, we find suggestive evidence of a small, negative impact on high school completion and college enrollment. However, for Black SE students more intensely affected by the Black disproportionality cap, we find increases in the likelihood of completing high school by 2% and enrolling in college by 4.6%. Although it is difficult to uncover the mechanisms driving this difference, our findings suggest that Black students in districts more intensely affected by the Black disproportionality cap are more likely to be misclassified for SE. We do not find similar effects for the Hispanic disproportionality cap.
3. Third, limiting overall SE enrollment and disproportionality also affected general education (GE) students. For students of any race in GE, we find that capping overall SE enrollment led to a 1.6% decline in the likelihood of enrolling in college. This result is likely driven by a combination of direct effects (GE students themselves are less likely to be placed in SE in later grades even when support is needed) and indirect effects (reducing the supports that SE students receive in the GE classroom leads to negative spillover effects for GE students; e.g., the GE teacher may need to give extra support to SE students, which could detract from GE students’ learning). Here, too, limiting Black disproportionality had the opposite effect on Black GE students’ outcomes compared to the overall enrollment cap. Reducing Black disproportionality improved the likelihood that Black GE students graduated high school by 1% and increased college enrollment by 2.5%.

Concluding Thoughts

Taken together, these results suggest that those who require SE services greatly benefit from receiving those services. We find large and meaningful impacts of SE services on high school completion and college enrollment for SE students who require services. However, those who are misclassified for SE can be significantly harmed. SE is an intensive and costly intervention, and it is important both to schools and students that individuals be appropriately placed in SE. We caution against the interpretation that capping Black disproportionality is necessarily the best policy intervention for reducing misclassification among Black students; instead, we point to the importance of considering the evaluation process and eligibility criteria for SE services to ensure that all students are appropriately classified for SE. While appropriately identifying students for SE is a difficult process, further investigating ways to improve evaluation criteria is likely to have long-term benefits for all public school students.