This paper reports the outcomes of an experimental evaluation of "Direct Instruction Spoken English (DISE)," an English language curriculum that focuses on developing English speaking, listening, and comprehension skills in English Learners (ELs). Twenty-nine middle schools in three states were randomly assigned to teach "DISE" Level 1 or their typical English language development program. Treatment teachers received two days of training and taught daily lessons. Project staff assessed 746 sixth and seventh-grade students with a proximal measure of English language proficiency and distal measures of language and oral reading fluency. Analyses of oral English language suggested differences between intervention conditions favored the DISE condition for students who began with lower English language proficiency and accumulated when taught over two years. Differences between intervention conditions were not observed after only one year of instruction and for students with advanced levels of English language proficiency. The findings suggest that an evidence-based English oral language program that included frequent teacher demonstrations and opportunities for students to practice speaking English may improve English oral language skills for middle school students. [This is the online first version of an article published in "Journal of Education for Students Placed at Risk (JESPAR)."]