The effects of content-related shared book reading on the language development of preschool dual language learners

• Children in a dual language preschool program participated in a content enriched shared book reading intervention.
• Participants were Spanish-speaking dual language learners.
• DLLs in the enriched shared book reading intervention grew in their content vocabulary knowledge.
• English and Spanish language proficiency were significant predictors of English vocabulary outcomes.

This study was designed to experimentally examine the effects of content-based shared book reading instruction on the vocabulary development of Spanish-speaking preschool children who were learning English as a second language. Using shared book reading as the mode of instruction, 42 preschool teachers and 252 children from their classrooms were randomly assigned at the class level to either a highly specified content-related book reading intervention or a practice-as-usual shared book reading condition. Children were screened using the preLAS® and were selected for the study based on their scores at the pre-functional and beginning level of English proficiency. Intervention teachers implemented the curricular intervention in small groups of 5–6 students, five days per week, for 20 min per session, for 18 weeks. Based on multilevel models, findings indicated significant effects of this intervention approach on proximal vocabulary outcomes with no significant effects on standardized vocabulary measures. Implications for practice are discussed.