Language and Literacy Trajectories for Dual Language Learners (DLLs) with Different Home Languages: Linguistic Distance and Implications for Practice

Using a large sample of longitudinal assessment data from children in publicly funded infant/toddler care, preschool, and kindergarten (analytic N = 453,468), this study modeled language and literacy trajectories from early infancy through kindergarten for dual language learners (DLLs) from homes representing many different languages and their peers from monolingual English-speaking homes. DLLs and their monolingual peers showed common developmental trajectories, including an initial period of rapid growth that slowed between 10 and 30 months, plateaued between 30 and 45 months, and then accelerated from 45 to 60 months of age. Although the general developmental patterns were similar, differences emerged between children in English-speaking versus non-English speaking homes: DLLs’ growth rates slowed more than their monolingual peers’ between 10 and 30 months but then grew more sharply after 45 months. A linguistic distance hypothesis helped to explain the magnitude of the differences between groups of DLLs and their monolingual peers. The differences occurred as children passed through specific developmental levels of the Desired Results Developmental Profile (DRDP) assessment’s learning progressions. The current study adds new quantitative information about language and literacy trajectories from early infancy through kindergarten among children from different language backgrounds and demonstrates how the findings may be applied to support effective instruction with culturally and linguistically diverse children.