Purpose The purpose of this study was to examine the difference between two bilingual program types: traditional early-exit and late-exit bilingual programs and academic achievement using archival data from the Texas Education Agency Public Education Information Management System. An examination of academic achievement rates across a 3-year period for students enrolled in these two programs will assist in analyzing the degree to which early-exit bilingual programs and late-exit bilingual programs influenced academic achievement in reading and math for English Language Learners in Texas public schools. Methodology This research investigation was a quantitative study with a causal-comparative research design in which differences were analyzed in the reading and math achievement (i.e., TAKS Reading and Math scores) of English Language Learners who had participated in either a transitional early-exit bilingual program or in a transitional late-exit bilingual programs. Archival data from the Texas Education Agency Public Education Information Management System were obtained for students in Grade 3, Grade 4, Grade 5, and Grade 6 for the 2008-2009, 2009-2010, and 2010-2011 school years. Data for each school year and for each grade level were analyzed separately, and then compared to determine the extent to which trends were present. Findings Of the 72 total statistical analyses conducted in this investigation, English Language Learners in late-exit bilingual education programs performed better than English Language Learners in early-exit bilingual education programs in 41 analyses. English Language Learners in early-exit bilingual education programs performed better than English Language Learners in late-exit bilingual education programs in 31 of the analyses. As such, results were not supportive of either the late-exit or the early-exit bilingual education programs as being more effective with respect to the reading and math achievement of English Language Learners in Grades 3, 4, 5, and 6. Accordingly, further research into the efficacy of transitional bilingual education programs is warranted. [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.]