GARDEN GROVE, Calif. (AP) -- When Thuy Vo Dang came to the U.S. as a young girl, her English took off. Her parents sent her to Vietnamese school on the weekends to learn her native language, but she eventually had to study it in graduate school to become fully literate.
Now, the 35-year-old mother of two and archivist for University of California, Irvine's Southeast Asian Archive has been lobbying for her Southern California school district to start the state's first dual immersion elementary school program in Vietnamese. She said she wants to help keep the language alive for the next generation.
"I can see how quickly they're forgetting their Vietnamese," Vo Dang said of her 7-year-old daughter and 3-year-old son. "I would love if this were available for him when he starts kindergarten."
The move to expand the use of Vietnamese in so-called dual immersion programs comes as the children of refugees who fled the aftermath of the Vietnam War are coming of age and striving to preserve the language for their American children. Nearly 1.9 million people of Vietnamese heritage live in the U.S., and a third were born here, according to census data.
In the last few years, schools in Texas and Washington have begun Vietnamese language dual immersion programs. Another is planned for Oregon in the fall and the Garden Grove Unified School District, which covers the area where Vo Dang lives, voted last month to consider starting a program in one of the country's largest Vietnamese immigrant enclaves.
Dual immersion programs teach students subjects ranging from math to social studies in English and another language. Classes are usually split between English speakers and English learners so that children model the languages for each other and work in pairs and groups to help each other with assignments.
Instructional time is split between the two languages depending on the program design and the age of the students. Most programs start in kindergarten and run through elementary school.
In the last few years, dual immersion programs have taken off across the country, said Julie Sugarman, senior research associate at the Center for Applied Linguistics. Several hundred programs were created during the 1990s, many of them in Spanish, and more recently the model has expanded to more languages, she said.
In Vietnamese communities, the programs target children who are native speakers of the language, but also the children and grandchildren of Vietnamese immigrants who may be stronger in English, and families with no background in Vietnamese who want to learn.
As immigration from Vietnam has slowed since the war, the number of English-speaking Vietnamese American children has grown.
Elders have worked to pass on the language by offering Vietnamese classes on the weekends. The number of students taking the extracurricular classes in Southern California has doubled to 15,000 in the last 15 years, said Quyen Di Chuc Bui, chair of the training committee for the Association of Vietnamese Language and Culture Schools.
Often new immigrants are so eager for their children to learn English quickly and succeed in school that learning their native language takes less priority. By the third generation, use of the language starts to decline unless there is an active effort to retain it, experts said.
In many communities, the English-speaking children of immigrants -- who may struggle to master their first language -- are leading the push for dual immersion, and the Vietnamese community is no exception.
"Many of these young parents are professionals, and they themselves felt the disadvantage of not being able to communicate in Vietnamese, and they want that for their children," said Kimoanh Nguyen-Lam, director of the Advanced Training and Research Division in the Office of International and Foreign Language Education.
Some of the biggest challenges to starting a program in Vietnamese are a lack of teachers with the appropriate credentials and a dearth of teaching materials at lower grade levels void of propaganda since many are published in communist Vietnam.
"We have to screen the material very carefully if we were to get material from Vietnam," said Uyen Tieu, dean of elementary instruction at Stafford Municipal School District near Houston, which started a program four years ago.
Proponents of dual immersion rattle off research that shows that English learners fare better learning in bilingual settings, and call the programs a win-win because English speakers acquire a new language and also excel.
Bilingual education is no stranger to controversy. Fifteen years ago, Californians voted to overhaul the way English learners were being taught in a move that slashed the number of bilingual classes around the state. In recent years, dual immersion programs -- which include English speakers as well as English learners -- have been on the rise in languages including Spanish, Mandarin and Armenian.