This research uses a descriptive quantitative statistical design to examine campus-level results from the State of Texas Assessments of Academic Readiness (STAAR). The focus is on describing the achievement disparities between campuses that implemented Transitional Bilingual Education (TBE) programs and those implementing Dual Language (DL) programs. By disaggregating the performance data, the study analyzes the mean STAAR performance of emergent bilingual (EB) students on campuses using TBE and DL models. It utilizes 2017-2019 campus and EB STAAR performance data for third through fifth grade in reading, obtained from the Texas Academic Performance Reports (TAPR). The following research questions will guide the study: (1) What are STAAR reading scores for emergent bilinguals in transitional bilingual education programs for third, fourth, and fifth grades? (a) Describe, compare, and analyze data for EB students in TBE programs from 2017-2019 in third, fourth and fifth-grade. (2) What are STAAR reading scores for emergent bilinguals in dual language bilingual education programs for the third, fourth, and fifth grades? (b) Describe, compare, and analyze data for EB students in DL programs from 2017-2019 in third, fourth and fifth-grade. (3) Do STAAR reading scores differ between transitional bilingual education and dual language programs for third, fourth, and fifth-grade emergent bilinguals? This research utilizes achievement gap metrics (Rodriguez et al., 2016; Stevens, 2017) to examine the TAPR report data and delineate the achievement disparities (effect size) between the mean performance of emergent bilingual (EB) students at schools with TBE programs and the mean performance of EB students at schools with DL programs in the context of the STAAR assessment. The comprehensive data gathered from diverse educational levels, encompassing district, state, and regional levels, unveils a striking disparity in academic outcomes between schools implementing Transitional Bilingual Education (TBE) and those embracing a Dual Language (DL) model. The findings illuminate that schools applying TBE did not attain academic results on par with other educational institutions, while those adopting a DL model achieved or exceeded the academic performance levels of the district, state, and region. Furthermore, a compelling pattern emerges when comparing the two bilingual models, illustrating the consistent superiority of schools utilizing a DL approach in academic performance over those employing TBE. These insights vividly underscore the efficacy of the DL model in providing bilingual education and fostering academic achievement among emergent bilinguals, surpassing the outcomes of TBE models. [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.]