Bilingual Children’s Vocabulary Development in English and Spanish: A Longitudinal Perspective

• In Event: Effect of Vocabulary on Literacy From Pre-K Through Grade 2: Spanish, Cantonese, and Tagalog English Language Learners

Abstract

Background. Vocabulary development has been identified as an important and challenging area of language and literacy development for English language learners (ELL) students (August & Shanahan, 2006). ELLs’ level of vocabulary knowledge has been shown to be an important predictor of reading ability, comprehension, and achievement on reading assessments (Carlo et al., 2004). Yet, recent research with ELL students also recognizes vocabulary as a domain of particular weakness (Páez et al., 2007). A research review shows that ELLs lag behind their English-speaking peers in depth and breadth of vocabulary knowledge (August et al., 2005). Longitudinal research is needed to understand the development trajectories for these students and identify areas of intervention to improve their literacy achievement (Gutiérrez, Zepeda, & Castro, 2010).
The purpose of this paper is to summarize the findings from a longitudinal study of Spanish-speaking children from low socioeconomic backgrounds. The study investigated the oral language and early literacy skills in Spanish and English from pre-K through the end of second grade for a sample of 340 bilingual children in the U.S. (ECS) and a comparison group of 150 monolingual Spanish-speaking children in Puerto Rico (PRC).
Methods and Data Sources. The sample was recruited when children were 4 years old and attended Head Start programs. Children were assessed as they entered and exited pre-kindergarten programs, at the end of kindergarten (n=329), first (n=301) and second grade (n=257). Data collection included four subtests of the Woodcock Language Proficiency Battery (letter and word recognition, vocabulary, language recalling skills, writing and spelling) and a researcher-developed phonological awareness task. Data collection also included information about home and school environment factors.

Results. The children in the sample demonstrated considerable variability in their dual language skills when assessed over time. Results show that, on average, children in the ECS sample performed below average in both English and Spanish when compared to monolingual norms and, despite early literacy and oral language gains, continue to lag behind monolingual children of the same age. Children in the ECS sample performed better in early literacy tasks than in oral language tasks in both English and Spanish. On average, the PRC sample scored significantly better than the ECS sample in Spanish oral language skills, but lower in phonological awareness skills.
Growth analysis of vocabulary skills for the ECS sample show that the rate of growth in English vocabulary (2.6 points per assessment) differs to the rate of growth in Spanish (.66 points). This growth pattern continues through second grade, as students are not making age-appropriate gains in Spanish while making some gains in their English. Additionally, four different groups of bilingual students were identified using cluster analysis and these groups exhibited significant differences in their growth rates.
Significance. This study has important theoretical and practical implications for schools and districts that are working with bilingual ELLs. Findings demonstrate that dual-language-learning children are a diverse group showing growth over time but might be at considerable risk for literacy difficulties given their oral language abilities. Educational and research implications are discussed.

Author

• Mariela M. Paez, Boston College