Classwide Extensions of Vocabulary Intervention Improve Learning of Academic Vocabulary by Preschoolers.

Purpose Many preschoolers, especially those from low-income households, would benefit from instruction to enrich their vocabulary and language repertoires. Yet, explicit instruction of vocabulary and language skills generally occurs infrequently in early childhood education settings. This study investigated the additive effects of teacher-led, classwide review strategies to a previously studied small-group intervention on children's learning of academic vocabulary. Method Participants included 23 children with limited oral language skills at risk for reading difficulties enrolled in single-case experimental designs. Effects of the classroom strategies alone also were examined in 10 children with above-average language abilities from 2 classrooms. Results Visual analyses of the adapted alternating treatments designs showed consistent learning improvements when vocabulary instruction was extended into the classroom for 12 children, ceiling effects were evident for 3 participants regardless of condition, and inconsistent or minimal effects were demonstrated by 8 participants. Multilevel modeling used to evaluate the effects statistically revealed strong treatment effects. In addition, the 10 children with above-average language showed impressive learning of vocabulary words from books subject to teacher review strategies in comparison to words from books to which they were not exposed. Teachers varied in the extent to which they implemented review strategies in their classrooms. Nevertheless, their responses to social validity assessments were positive, supporting the feasibility of this intervention. Conclusions The addition of classwide review and practice opportunities is an effective means of enhancing the effects of an easy-to-implement small-group intervention that teaches challenging vocabulary words within prerecorded stories. This approach holds promise as a way to shrink the pervasive word gap that typically exists when children in high-poverty communities enter school.