The purpose of this study was to evaluate the impact (positive, negative, or neutral) of Accelerated Readers (AR), a standard based intervention, on the academic achievement of English Language Learners at Carolina Herrera Elementary School. Carolina Herrera Elementary School, was analyzed using these specific lenses: (1) curriculum and instruction, (2) research-based strategies, (3) expectations for student learning, and (4) data-driven decision-making. The summative evaluation portion included a pre-post independent groups designs and a nonequivalent benchmark group design using a high performing school that has similar demographics. The pre-post design was used to access improvement at the experimental school from the 2007 to the 2008 school years. The nonequivalent group design was used to compare the post-test results of English Language Learners in Grade 2 through 5 at Carolina Herrera Elementary School (experimental group) and Elijah Flores Elementary School (benchmark group). California State Standards Test Scores (CST) of "far below basic, below basic, basic, proficient, and advanced" were converted to a numerical scale ranging from "0" through "4" to correspond to the CST proficiency band scores. Achievement at Elijah Flores Elementary School was also benchmarked. The school was chosen as a benchmark school because it has a large Spanish speaking ELL population yet has historically outperformed similar schools. The information and the data utilized for this study was based heavily on quantitative data (CSTs), but also included some qualitative data. The experimental group included all students enrolled in grades 2-5 who were identified as ELL in an urban elementary school. The 2007-2008 academic year was selected as the baseline because it was the final year that AR was used as the core curriculum of the school before a change in administration. Quantitative findings indicated a statistically significant positive change from 2007 to 2008 in the 2nd grade and a significantly negative change in the 4th grade. Overall, the change from 2007 to 2008 was both statistically and practically non-significant. Teacher interviews suggested that while there were many positive aspects to AR, it did detract from the amount of time spent on the core curriculum. The results of this study suggest that the impact of Accelerated Reader standards on ELL learner achievement is minimal, possibly because it did not allow sufficient time for the core curriculum, Houghton-Mifflin. Further, the qualitative teacher interview findings suggested that the intervention interfered with the core curriculum, Houghton-Mifflin. While AR does lends itself to being a useful resource to assist students into moving into the "proficient" and "advanced" proficiency bands, steps need to be taken to make sure that sufficient time is devoted to direct instruction in a core curriculum. [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.]