In Utah, 9 percent of the state’s public elementary students are enrolled in dual-language programs. In Portland, Ore., 10 percent of all students, and nearly one in five kindergartners, participate. Statewide efforts to increase the number of programs, and expand access to them, are underway in states including Delaware and North Carolina.

Libia Gil, assistant deputy secretary and director of the office of English language acquisition at the federal Education Department, said that while there was no definitive count of dual-language programs nationwide, “there are clear indications of a movement.”

In some localities, like New York City, the primary goal of expanding dual-language programs is to increase access to them for English-language learners, officials at the city’s Education Department said.

Traditionally, these children were taught almost exclusively in English. But new research suggests that while these students can take more time to get on grade level in a dual-language program, by late elementary or middle school they tend to perform as well as or better academically than their peers and may be more likely to be reclassified as proficient in English.