PROVO, Utah — In this deeply Mormon state, the school day is being translated into Chinese. Strains of Taiwanese pop songs float through the hallways. School cafeterias serve dumplings. Third graders pass notes in Mandarin. And when visitors enter a classroom, the students shout, “Ni hao!”

“If I close my eyes, I see a room full of Chinese children,” said Colleen Densley, the principal of Wasatch Elementary School here in central Utah, recalling the words of one amazed teacher. “If I open my eyes I see my American students.”

For generations, Mormon missionaries from Utah have crisscrossed the globe and returned home speaking Tagalog and Xhosa. Now, with hopes of preparing students for a competitive world economy, the state is building one of the largest and most ambitious school-language programs in the nation.

Dual-language classes have existed for years, but they are now growing fast in many states as an outcry against bilingual education fades and educators look for ways to prepare American students for a polyglot global job market. But few have embraced the idea with such unlikely zeal as Utah, a state that passed an English-only law in 2000 and routinely ranks last in the nation on education spending,according to United States Census figures.

In foreign languages, however, Utah now sees a highway to the world economy. Republicans in Salt Lake City, the state capital, have pledged millions for the program. Four years after it began, nearly half of Utah’s 41 school districts offer programs in which elementary school students spend half the day learning in English and half in a foreign language. There are 14,000 students enrolled and 20,000 signed up for next year.

In Utah, where economic growth is being driven by surging exports of gold and silver, airplane engines and computer memory, industry leaders say a bilingual work force could help lure international companies to the state and would make Utah’s graduates stronger candidates for jobs in, say, Beijing, London or São Paulo.

Educators and parents say the program is about academic development, not preparing Mormon students to proselytize overseas. Yet they said Utah’s immigrant communities and the overseas peregrinations of its large Mormon population make it fertile ground to teach foreign languages.

“From the very beginnings of Utah, it’s been part of our culture,” said Gov. Gary R. Herbert in an interview, “the missionary effort of going out and living in foreign lands.”

The dual language programs start in first grade, and will eventually extend through middle school, with students taking advanced placement tests in ninth grade and then studying at a college level through the rest of high school. Right now, they can take classes in French, Spanish, Portuguese and Mandarin. German is likely to be next, and educators have discussed Arabic.

Most of the programs are designed to teach native English speakers. But in corners of the state with more Latino immigrants, the state has also set up classes where Spanish speakers are taught together, in both English and Spanish.

Studies of other immersion programs have found that students do just as well, or better, on standardized tests as students in English-only classrooms, with the added bonus that they picked up a new language while learning state capitals and multiplication tables.

“There’s no way to learn another language as easily or as successfully,” said Myriam Met, a consultant who has worked on Utah’s immersion programs.

The teachers — most of them from other countries — teach regular subjects like mathematics and reading and social studies, only speaking exclusively in a foreign language. At first, they pantomime and use pictures and videos to get their point across, but they say the students can understand them within a few weeks.

Students in the immersion programs are graded normally, and have to take the same standardized tests as their peers. That can pose a problem in areas like science. Schools have to make sure that students who learned the Mandarin words for “photosynthesis” and “chlorophyll” can also recognize the terms on an English-language standardized tests.

So far, however, the program has amounted to a transformation. At Chinese-speaking schools, red paper lanterns dangle from the ceiling like ripe fruit, and maps of China are taped to the wall. Taiwanese and American flags hang in classrooms. Cafeterias serve pot stickers, and schools celebrate the Chinese New Year.

At Lone Peak Elementary in the town of Sandy, students grooved along one morning as their teacher played a Chinese hip-hop song. The school’s principal, McKay Robinson, stood at the back of the classroom, keeping quiet, mindful not to break the rule posted on the classroom door: “No English Please.”At Wasatch Elementary, where 360 of the school’s 860 students are in Mandarin immersion classes, officials made the faculty lounge an English-only zone so all the teachers could understand one another.

Parents, wary at first, have rushed to enter lotteries to place their children in the programs. Some school districts have waiting lists 100 students long. Some parents drive 30 miles to bring their children to class, or have even moved to be closer to an immersion school.

Holli Gardner knew the classes had taken root when her first-grade son, Talan, said a prayer before dinner in Portuguese. Jody Katz’s two sons, Jonah and Simon, will whisper to each other in Mandarin.

“This is something I could never teach my kid,” said Alison Memmott, 41, whose fourth-grader, Ella, has been studying Mandarin since she was in first grade.

A few months ago, Ms. Memmott’s family attended an exhibition by visiting Chinese artists in Salt Lake City, and Ella chatted up one of the artists in Mandarin. Within a few minutes, Ms. Memmott said, all of the artists were laughing and joking with the girl and invited Ella to return to Beijing with them.

“They said there are lots of boys in China she could marry,” Ms. Memmott said. “I said no thanks.”