To Improve Outcomes for Students with Disabilities, Invest in Teacher Retention

Decades of research demonstrate that teacher turnover negatively impacts students' academic achievement (e.g., Hanushek et al., 2016; Ronfeldt et al., 2013), with ripple effects that can move throughout a school (McLeskey & Billingsley, 2008; Harbatkin et al., 2025). In a new study from CALDER/SPARC Center, researchers analyzed data from Washington state (2009-2019) to examine how teacher turnover specifically affects students with disabilities (Kaler et al., 2025). Controlling for school, principal, and year-specific factors, they found that turnover negatively impacts all students but disproportionately affects students with disabilities—particularly when special education teachers depart.