The purpose of this study was to examine the short and long term effects of a Two-Way bilingual education program on the literacy development of students in K-3 and high school. Two groups included students in English Language Learners (ELL) as well as students who were not ELL. Both groups were instructed in equal 50-50 percent English/Spanish. The academic performance of these students was focus on short-term look at grades K-3 but also follow groups of students through the middle and high school years. Results indicate that there is little difference between programs in the early grades but also the researchers found "very large, cumulative, long-term differences in student achievement; these students were in Two-Way bilingual program during their elementary school years" (Thomas and Collier, 1998, p. 49). Results show that students in the ELL program make adequate academic progress, confirming the usefulness of the Two-Way bilingual program in reducing the achievement gap between ELL students and others. Educators who use the enrichment models that were initially developed for English learners are beginning to see the power of these models for students.