The impact of an instructional intervention on the science knowledge and academic language of middle-grade English as additional language (EAL) learners and their English proficient classmates

This waitlist control study assessed the effectiveness of an intervention to develop the science knowledge and academic language of English as an additional language (EAL) learners and their English proficient classmates. The intervention employed an inquiry approach to teaching science and evidence-based methods to support EAL learners. Over two years, nine schools participated in the study. The first year of the study was designed as a school-level randomized control trial, where schools were randomized to treatment or control conditions. The second year was a quasi-experiment in which all schools implemented the intervention, and gains in the year 2 treatment schools were compared with treatment and control gains in year 1. Findings indicated that the pooled sample of treatment students performed better than the pooled sample of control students on CBM science and academic assessments in both years and on the standardized academic language assessment in year 2. Effects for subgroups indicated that while English proficient students outperformed control English-proficient students in science and academic English in both years, this was not the case for EAL learners who only outperformed control EAL learners in academic language in year 1, possibly because of the smaller sample size for EAL learners.