Learning vocabulary via computer-assisted scaffolding for text processing

A substantial amount of literature regarding first language (L1) acquisition has shown that reading for meaning significantly contributes to vocabulary expansion and strongly relates to overall academic success. Research in the English as a Second Language (ESL) context, however, has presented mixed results, in particular for recent immigrant students in North America. This is due to the large gap between their vocabulary knowledge and reading ability and their urgent need to acquire English academic language in order to meet grade requirements in the school. This study investigates ESL students' vocabulary learning outcomes through reading facilitated by a computer-assisted language learning (CALL) program that supports their word recognition ability. It focuses on the differences in their understanding of target words in both their first and second languages (L2) that have rarely been studied. The results from both monolingual and bilingual receptive vocabulary tests show that the students learned more words with access to computer-mediated dictionaries than without; however, the variations in their vocabulary learning in the CALL environment were found to be related to their English skills and conceptual knowledge of target words in their L1. Bilingual vocabulary tests demonstrate great potential, as a more sensitive assessment measure, in accurately evaluating ESL students' vocabulary learning progress, given their atypical language development trajectory which is different from monolingual native English-speaking students.