The educational rights of students learning English as an additional language have been federally protected for over 40 years. Since the landmark case of Lau v. Nichols (1974), language has been acknowledged as playing a central role in ensuring that English language learners (ELLs) have equal access to academic content (Hakuta, 2011). These same years have seen numerous shifts in educational policy that have dramatically changed the ways in which ELLs are assessed for progress in learning English and core content areas. The reauthorization of the Elementary and Secondary Education Act (ESEA) under No Child Left Behind (NCLB) created heightened accountability provisions for ELLs (Abedi, 2004), and more recently, the College and Career Readiness (CCR) standards have elevated and made more explicit the language demands of content learning for all students, with particular consequences for ELLs (G. C. Bunch, Kibler, & Pimentel, 2012; Moschkovich, 2012; Quinn, Lee, & ValdA(C)s, 2012). New emphasis has also been placed on the need for measuring English language proficiency (ELP) and on clarifying what decisions can be reasonably made from ELP assessments (Abedi & Levine, 2013). From identification, classification, placement, and instruction, to exiting from ELL status, the need for information about ELLs' language proficiency is critical for informing a vast range of decisions that affect their educational opportunities and outcomes.
Program Evaluation and Effectiveness