This action research seeks to determine the impact of teacher training and the use of specific instructional strategies, per the research-based SIOP® teaching model, on English language arts achievement of formally identified first grade English Learners. The study aims to discover if using strategic techniques to teach vocabulary positively affects language acquisition and comprehension. English Learners have historically lagged behind grade level peers in all academic areas. English Learners tend to have many outside variables that can affect their ability to focus on school. Issues with immigration, class, culture, and race are all relevant topics with this population. This study discusses many of these issues present both in and outside of the classroom. The action research involved a series of professional development sessions, organized and implemented by a certified SIOP® coach, in this case the action researcher, which included specific strategies on how to foster vocabulary acquisition. Through a series of non-evaluative observations and opportunities for reflection, teachers collaborated in order to refine their practices. Both quantitative and qualitative data were gathered to determine the effectiveness this model, knowing that it is limited in scope due to the sample size and the time parameters involved with this study. However, this study provided insight into best practices in supporting language instruction and suggested opportunities for additional research. The goal of this study was to determine if being strategic in how and what we teach English Learners fosters student engagement within their classroom community. The ultimate goal being that this knowledge can help level the playing field in terms of understanding and accessing grade level and beyond content so that these diverse learners can achieve academically. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]