Exploring effective vocabulary instructional strategies for ELLs through online professional development

The number of English language learners entering the American public school system is on a continual rise. While there remains a shortage of certified English as a Second Language (ESL) teachers, research has also shown an overall lack of preparation for mainstream classroom teachers to effectively deal with such an influx. As a result, teachers enter the education field, and subsequently the classroom, with their own biases, perceptions, and knowledge, or the lack thereof, of how to successfully teach English language learners (ELLs). The purpose for the study was to implement an online professional development book study to improve the instruction practices of mainstream elementary schoolteachers and content area middle school teachers, who instructed ELLs, with the expectation of improving ELLs' vocabulary knowledge. The study determined the effect of the professional development experience on teachers' knowledge and perceptions toward teaching ELLs through on online survey and meeting discussion chat rooms through My Learning Plan, and assessed students' growth through a computer-adaptive reading test through STAR Renaissance, a web-based assessment. Using the theoretical backdrop of theorists Vygotsky (1978, 1979) and Krashen (1981, 1982, 1985), and the differentiated instruction model, this paper sought to answer the research questions of how participating in an online book study affected teachers' instructional practices and how those practices affected ELLs' vocabulary knowledge.