Abstract
Previous research indicates that joint storybook reading between caregivers (parents or teachers) and children can have positive effects on the oral language development of young children (Whitehurst et al., 1988; Dickinson & Smith, 1994). This study aimed to add to this body of research by providing information on the relationship between teachers’ language complexity and vocabulary strategies used during storybook reading and vocabulary outcomes for monolingual and dual language learners in linguistically diverse Head Start classrooms. Videotapes of 23 Head Start teachers were coded and analyzed for vocabulary instruction strategies and language complexity during storybook reading using hierarchical regression techniques to determine how these factors related to gains in student vocabulary over the course of a year. Students’ oral language was assessed using the Peabody Picture Vocabulary Test (PPVT) and the Learning Express vocabulary sub-test (LE). Teacher’s language complexity was calculated with respect to both quantity (mean length of utterance) and quality (type/token ratio and use of uncommon words). Teacher’s use of vocabulary strategies was examined with respect to the words chosen for instruction and the strategies used to instruct those words. Overall, teachers in this study tended to choose high utility words to instruct, but the strategies used to teach those words, and the number of words chosen for instruction, were often not optimally aligned with best practices in vocabulary instruction (Beck et al., 2002). For the PPVT outcome measure, teachers’ use of higher numbers of vocabulary instruction strategies per word was differentially related to students’ vocabulary outcomes based on the student’s prior vocabulary knowledge, such that the use of more vocabulary instruction strategies per word was negatively related to vocabulary outcomes for students who began the year with the smallest vocabularies. There was also a significant interaction between teachers’ use of uncommon words and students’ prior vocabulary knowledge, though this relationship was only statistically significant for the PPVT outcome. Teachers’ use of more complex language was differentially related to students’ outcomes. Students who began the year with the lowest vocabulary levels exhibited a positive relationship between the teacher’s use of uncommon words and vocabulary outcomes, while average or higher vocabulary students showed a negative relationship between increased exposure to these uncommon words and their vocabulary outcomes. The implications for teachers’ professional development are discussed.