English Learners experience challenges related to comprehension of science text particularly at the high school level. The language of science differs significantly from that of conversation and expository text. Students benefit from collaborative interpretation of readings. Additionally, there appears to be a need to train adolescents in the oral language skills requisite for academic discourse. This study employed a sample of high school physical science students (N = 75) whose first language was Spanish and who were currently developing English language proficiency. It used quasi-experimental methodology with treatment and comparison groups, during the normal operations of the public school classroom. It tested the effect of training with a textbook summarization method and with an academic conversation strategy on the comprehension of state-adopted science textbook readings. Posttest scores of both groups were analyzed using an ANOVA. Posttest scores of treatment group members were analyzed in relation to prior science knowledge, reading level, gender, and level of English proficiency using a factorial ANOVA. Findings suggest that the treatment had a positive impact on the achievement of students who had a low level of English language proficiency. In light of the at-risk nature of this population, given low socioeconomic status and that a high percentage of families are migrant workers, this in encouraging. The basic premise of the treatment appears promising. Evidence collected pertaining to its effect relative to students’ general ESOL level, science background knowledge, literacy skills, and gender neither confirmed nor denied the viability of the strategy. The further significance of this study is that it adds to the body of research on strategies to support English Learners.