With the onset of No Child left behind legislation, the English Language Learner (ELL) subgroup gained new attention. Schools and districts failing to meet accountability targets began to seek out programs and strategies that would better ensure the academic progress of those students who were learning grade-level content while learning English. This study examines one schools attempt at increasing the reading achievement of ELL students in grades three and four. This study explores the impact a treatment had on English reading achievement. It specifically asked if 30 to 45 minutes of formal English language development instruction had an impact on students' English reading fluency achievement and reading comprehension achievement. According to the data collected in the study, the impact formal English language development had on English reading fluency yielded insignificant results. The study found significant results in the area of reading comprehension. The study found reading comprehension gains at the significance level 0.042 for third grade students in the experimental group. These results were not replicated at the significance level for fourth grade students. The cohort of students who were enrolled in the study for two years, showed significant increases, at the 0.01 level of significance in the percent of students reaching reading comprehension target scores. There were not any significant findings in the gains made with these students in the area of reading fluency. Formal English language development instruction delivered over one school year was shown in this study to positively impact reading comprehension achievement and to have insignificant impact on reading fluency. [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.]