The effects of two curriculum interventions on the academic achievement of English language learners

English language learners (ELLs) comprise a rapidly growing subgroup within the K-12 student population and schools struggle to find instructional programs that can effectively teach both English and academic content. The study explored the differences in academic achievement for students enrolled in two popular and successful instructional programs, an English-only (ESL) or a dual language immersion (DL) program. The purpose of the study was to determine the extent to which pre-test proficiency level, gender, race, and identification as a student with disabilities (SWD) accounted for the variability in academic achievement for students enrolled in an ESL or a DL instructional program. Stepwise multiple linear regression analyses were used to determine the extent of variability in academic achievement accounted for by pre-test proficiency level, gender, race, and identification as student with disabilities (SWD) for students enrolled in an ESL or DL instructional program in five academic areas; overall proficiency, reading proficiency, writing proficiency, listening proficiency, and speaking proficiency. Regression analyses revealed that SWD was a significant variable accounting for the largest percentage of variability no matter the instructional program. The data also demonstrated that the independent variables accounted for more variability in achievement for students enrolled in a DL program versus students enrolled in an ESL program. Further analysis revealed that ESL students had greater gains in proficiency than DL students in three out of the five academic areas studied. Implications for practitioners and further research based on the findings are also presented in the study.