The Deseret News (Utah) has an article “Language immersion classroom: Programs are popular, diligence translate to performance” by Mercedes White that revues some of the research on foreign language immersion programs (here):
….. In 1981 there were fewer than 30 immersion programs in the country, today there are 448, according to a 2011 report released by the Center for Applied Linguistics (CAL), a non-profit organization that advocates for foreign language instruction. States like Minnesota and Utah are leading the way with 52 and 58 schools offering language immersion options. American students are being educated in Spanish, French, Mandarin, Japanese, German, Arabic, and Norwegian.
One of the most intriguing aspects of these programs, both for parents and educators, is that immersion students tend to outperform their English-only peers on standardized tests. Why this phenomena exists is not entirely clear, but several factors unique to these programs provide some insight. Learning a new language simulates brain development in ways that enhance mental flexibility and develop problem solving skills says Ellen Bialystok, a research psychologist at York University in Toronto Canada. Parents with children in immersion programs may be more invested in their kids education, which has strong positive impact on student achievement notes Fatima Baig an education researcher at the University of Iowa. Finally, the nature of language immersion teaches students how to stick to difficult tasks. This diligence translates to better performance on exams, because students will be more likely to persist on challenging problems, according to a report released by the department of education at the University of Pennsylvania….
"Children who were from socio-economically underprivileged backgrounds benefited from immersion instruction as much as their more affluent peer."
And, for Oregon’s Governor Kitzhaber and other educators focused on getting high school graduation rates up among underperforming students, foreign language immersion programs could help:
….. In a study of French immersion students in the Cincinnati Public School system researchers found that children who were from socio-economically underprivileged backgrounds benefited from immersion instruction as much as their more affluent peers. "Bilingual education helps to level the socio-economic playing field by giving students from disadvantaged backgrounds the opportunity to acquire and excel in another language ... in some cases (they) perform as well as students from more advangtaged backgrounds," said Fred Genesee, researcher on the study, from his office at McGill University in Montreal, Quebec.
"Bilingual education helps to level the socio-economic playing field by giving students from disadvantaged backgrounds the opportunity to acquire and excel in another language..."