ABSTRACT School districts in the United States have undergone large changes over the last decade to accommodate No Child Left Behind (NCLB). Arizona accommodated NCLB through Arizona's Instrument to Measure Standards (AIMS). Expectations were established for all students, varying by group of students based on grade, special education status, free/reduced lunch status, and English Language Learner (ELL) status. AIMS performance for subgroups has been scrutinized, due to the high stakes for schools and districts to meet expectations. This study is interested in the performance of ELL students, when compared with non-ELL students. The current study investigated AIMS performance of students in grades three through six from a large Arizona school district with predominantly low SES, Hispanic students. Approximately 90% of the students from this district were classified as ELL during their first year in the district. AIMS scores in Math and Reading were compared for ELL and non-ELL students across the years 2008, 2009, and 2010. Results suggest that there are differences in performance for ELL and non-ELL students, with ELL students scoring lower in both Math and Reading than non-ELL students. Additionally, ELL and non-ELL students showed similar performance across time in Math, with an increasing number of students Meeting or Exceeding the standards from year 2008 to 2009 for both ELL and non-ELL students. Student performance in Math for ELL and non-ELL students did not continue to improve from 2009 to 2010. On Reading performance, greater proportions of students scored as Meets or Exceeds across time for ELL students but not for non-ELL students. Non-ELL students scored at Meets or Exceeds at equal proportions across time, although non-ELL students scored at Meets or Exceeds in higher proportions than ELL students for all three years. Results suggest the need for continued research into the appropriateness of the AIMS for ELL students and more detailed comparisons of ELL and non-ELL students within and across districts with high proportions of ELL students.