“…Currently, 1,500 schools in approximately 600 school districts across at least 24 states operate on a four-day school week schedule (Thompson, et al, 2019) Despite the growing use of these school schedules nationwide, little causal evidence exists on the effects of these policies on school, community, and student outcomes. To date, a handful of studies have conducted quasi-experimental analyses of the unintended effects of four-day school weeks on student achievement (Anderson and Walker, 2015; Thompson, 2019), juvenile crime (Fischer and Argyle, 2018), and maternal labor supply (Ward, 2019), but this is the first study to causally examine the direct effects 1 While these approaches have helped these school districts become more financially viable, many of these -increasing class sizes (e.g., Krueger, 1999), closing schools (e.g., Engberg, et al, 2012), and financial intervention systems (e.g., Thompson, 2016) in particular -have been found to negatively impact student achievement. of four-day school weeks on cost savings.…”