Abstract
With the increasing number of children enrolling in early childhood classrooms (ECC), it is important to understand not only the language environment in children’s homes, but also the language exposure that takes place in educational settings. The first study of this thesis is a baseline phase to an interventional study assessing the effect of an oral language intervention Enhancing Rich Conversation (ENRICH) on educator-child interactions. We aimed to analyse the linguistic aspects of these interactions in 24 New Zealand ECCs, sampling 25 minutes of naturally occurring interaction across five contexts: book-reading, mealtime, play, group, and nappy change. We assessed the quantity (e.g., total utterances) and quality (e.g., lexical diversity, mean length of utterance in morphemes) of educator-toddler talk. The findings revealed that the language between the educators and toddlers varied depending on the context. For instance, educators’ speech was higher in quantity and lexical diversity during book-reading sessions than other contexts. However, educators’ mean length of utterance in morphemes (sentence complexity) was highest during nappy change.
The second study builds upon the first study by examining the long-term impact of an oral language enrichment program (ENRICH) on linguistic aspects of educator-child interactions. The same twenty-four centres were randomly assigned to either the ENRICH or Active Control condition. Educators in ENRICH received two professional development workshops and resources, while those in Active Control attended two webinars on children’s nutrition. Video footage one year after baseline (one-year follow-up) was collected for a total of 25 minutes per centre across the same five contexts: book-reading, mealtime, play, group, and nappy change and compared to baseline. Similar to the baseline phase, we assessed the quantity and quality of educator-toddler talk from a linguistic perspective. We found effects of ENRICH for educator-child interactions in book-reading and nappy change, with children using more utterances and educators engaging in shorter turns with children during book-reading. Additionally, educators in the ENRICH condition used less complex language during both book-reading and nappy.
Given the relatively high proportions of non-English speaking children in the first two studies, there is a need to develop assessments in New Zealand for non-English languages and to explore how these bilingual/multilingual children language develop as a function of various factors. The third study investigated predictors of variability in Mandarin- and Cantonese-speaking children’s language development and aimed to validate Mandarin and Cantonese language assessments for New Zealand children. Over 200 mothers in the Growing Up in New Zealand longitudinal cohort study reported that their two-year-old children could understand Mandarin and/or Cantonese. They were asked to complete the vocabulary and grammar checklists for New Zealand Mandarin and Cantonese speakers at the Age 2 data wave. Children's vocabulary and grammar development at two years old were assessed as a function of gender, socioeconomic status (area-level deprivation), maternal education, birth order, language status, and maternal concerns. The results showed that maternal education, household deprivation level, and birth order were significant home factors associated with the children’s vocabulary and grammar skills. Furthermore, language status and whether the mother had any concerns were also unique predictors of the children’s vocabulary development in Mandarin and Cantonese. Specifically, monolingual children with no concerns from their mothers demonstrated higher Mandarin and Cantonese vocabularies.
Together, this thesis contributes to the sociocultural framework of child development by demonstrating the roles of instructional settings, contexts, and teaching practices in toddler language acquisition.