The state of Arizona required all K-12 teachers and administrators to complete a 15-hour training Structured English Immersion (SEI) by August 31, 2006. The purpose of the study was to determine if the SEI endorsement was meaningful to K-12 teachers. The research problem was that there is currently no research or data demonstrating the impact or effectiveness of the SEI requirement on student performance. The focus of the SEI was to help teachers instruct content while understanding second language processes for English Language Learner (ELL) students. An outcome of the SEI goals would assist the ELL students in meeting Adequate Yearly Progress (AYP) as deemed by NCLB. The researcher completed a survey and analyzed the ELL AIMS reading scores using data from the year before and after the provisional SEI requirement. A One Sample T-Test was used to analyze the data. The mean was discussed to determine the significance of the research questions. Perceptions of the teachers showed a belief to support ELL students yet concern on the lack of support and design of the SEI training. The findings show that the SEI training does not support the level of instruction and knowledge needed to fully support ELL students when teaching reading. The research provided insight on the role of the SEI endorsement and influence of ELL reading scores, teacher perceptions of the requirement, and overall beliefs on the role of the SEI endorsement in relation to reading, the use of ELL standards, and AIMS scores.