Dual-language-immersion students in Portland, Ore., outperformed their peers in English-reading skills by a full school year’s worth of learning by the end of middle school.
The scientific term for a finding like that—in an education research world where a few weeks’ learning is often considered a significant intervention—is “whooo-boy.”
Those are the preliminary conclusions of a four-year, randomized trial of the dual-language program by the research firm RAND, the American Councils for International Education, and Portland public schools.
About 10 percent of the district’s 46,000 students attend dual-language programs in Spanish, Japanese, Mandarin Chinese, Russian, and Vietnamese. Seats are oversubscribed and assigned by lottery, which allowed researchers to run a randomized trial of about 1,600 students who started kindergarten in 2004-2010. Schools that operated dual-language-immersion programs had comparable class sizes and resources.
Researchers compared students who were randomly assigned to the immersion programs to those who had applied unsuccessfully for the lottery. Those who participated in the immersion programs scored significantly higher on the Oregon Assessment of Knowledge and Skills in reading; by the equivalent of seven months of learning by the end of 5th grade and by nine months of learning by the end of 8th grade. Students who were native English speakers got the same boost as ELLs. There was no benefit, but also no negative effect, on immersion students’ scores in math or science.
“It is kind of striking,” said Jennifer Steele, associate education professor at American University, and RAND’s primary investigator for the study. She noted that the district had adopted the programs not strictly as a way to boost English-learners, but to close achievement gaps in general and move to a “strength-based” rather than a “deficit-based” intervention system.
“Part of the way Portland sees the issue, really is about ensuring schools and classrooms are diverse and people really benefit in a tangible way from that diversity,” Steele said. “It is about kids learning from each other; the language you bring to that class is treated as an asset and the languages you get from your peers is also an asset, because more languages are better than fewer.”
Not Just for English-Language Learners
In two-way immersion programs, students start out in kindergarten learning 90 percent of the time in their native language, and 10 percent of the time in the language they are learning. The proportion of time spent in the second language increases 10 percent each year, until students in grades 4 and up learned for half of their time in each language.
“When you are shifting back and forth between languages, your ability to do those cognitive shifts is strengthened. The estimates are pretty small and discrete, and it’s in terms of millisecond response time,” Steele said. That might not be a lot to start with, she said, but benefits build over time, as students have an easier time understanding the underlying structure of linguistics “which potentially helps them to be better at unpacking and comprehending texts.”
Moreover, for students who started out as English-language learners, those who attended dual-language programs were 3 percentage points less likely to still be an ELL by 6th grade. If their native language matched the school’s partner language, such as a Chinese ELL student attending a Chinese-English immersion program—they were 14 percentage points less likely to be an ELL by 6th grade, compared to students who didn’t participate in the dual immersion.
“Dual-language can easily go to just serving English-only kids, or just serving students with a priority of needs,” said Michael Bacon, assistant director of dual-language programs for the Portland district. “Knowing there’s a win-win, there’s a benefit for both groups, is so important.”
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