New What Works Clearinghouse Intervention Report on Dual Language Programs

The What Works Clearinghouse (WWC) recently reviewed the research on dual language programs, in which classroom teachers instruct students from an early age and over multiple years in both English and a second, partner language. The results are summarized in an intervention report released today by IES. Dual language programs can help native English speakers develop proficiency in a second language and English learners develop proficiency in both their native language and English. These programs vary widely by partner language, primary language of the student population, and duration. Because reaching proficiency in a second language may require substantial exposure over an extended period of time, the report examines dual language programs that (1) span at least the elementary grades and (2) provide at least 50 percent of instruction in the partner language. Dual language programs can be implemented with students from one language group (in one-way programs) or with students from two language groups (in two-way programs). The two studies summarized in the report implemented both types of programs. In one study, schools included in the sample implemented nine one-way programs in Japanese, Mandarin, and Spanish and 13 two-way programs in Russian and Spanish in elementary and middle schools. In the other study, schools implemented 17 one-way programs in Chinese, French, and Spanish and nine two-way programs in Spanish in elementary schools. More high-quality research is needed to understand the effects of dual language programs in varied contexts. The WWC reviewed many studies for this intervention report, but only two studies meet WWC standards. The two studies included 3,133 students in Oregon and Utah. Nine percent of the student sample were English learners. Based on the two studies that meet WWC standards, the WWC found moderate evidence that dual language programs positively impacted student literacy achievement in English, compared with instructional programs in English only. The WWC found uncertain effects on science and mathematics achievement. Read the full dual language programs intervention report and learn more about the studies that contributed to this report. To see other WWC reports, visit whatworks.ed.gov and check your inbox for more updates and new releases throughout the year. For the latest WWC news, follow the WWC on Twitter and Facebook.