This qualitative study centered on science instruction and learning that occurred in a Title I elementary school in a suburban district in southeast Texas. Twelve teachers were interviewed in order to understand their perceptions of their classroom practices in terms of science instruction and learning for English Language Learners (ELL). This study also analyzed information gathered from teacher lesson plan and classroom observations. The participants' awareness of the instructional practices necessary for ELL student achievement in science was evident through analysis of interview transcripts. However, after observation of actual classroom instruction, it became apparent that the teaching and learning in most classrooms was not reflective of this awareness. This study proposes that this disconnect may be a result of a lack of quality professional development available to the teachers. The study also outlines and describes the characteristics of quality professional development and its relationship to focused instruction and continuous student improvement. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]