Paul and Denise Gamble have never been to China, and they were never particularly interested in its language or culture. Yet their two school-age children attend Shuang Wen Academy, a public school on the Lower East Side where much of the day is spent learning Mandarin.

Their children are part of an unexpected phenomenon at the four-year-old school: while most are children of Chinese immigrants, almost 10 percent of the students are black, and many of them come from the outer reaches of the city, enduring long trips for the chance to attend a school that has developed a reputation for excellence.

''When I tell my friends that my children are in a bilingual school learning Mandarin, some are shocked,'' Ms. Gamble said. ''Some think I'm crazy. Some ask, 'Why would you do that?' Well, I just want my children to have a good education.''

Shuang Wen is one of more than 150 small public schools established in the late 1990's as an alternative to larger, impersonal public schools. The school, whose name means dual language in Chinese, has many teachers who believe in dual-language education, and its goal is to teach students Mandarin and Chinese culture.

Although only two of the school's first class of 45 students were not of Chinese descent, Shuang Wen gradually gained a reputation among some of the city's black middle-class parents for being nurturing yet rigorous. In last spring's citywide third-grade math and English tests, Shuang Wen ranked third in math and 23rd in English among the city's almost 1,000 elementary schools.

Now, before the start of every school year, more and more black parents arrive at the office of the principal, Ling-Ling Chou, seeking admission for their children to the prekindergarten class -- which is based on interviews with prospective students and their parents. They are undeterred by the fact that their children will be among the few non-Asians in the school, or that Mandarin is famously difficult to master. Chinese instruction runs from 3 to 5:30 p.m. daily. All subjects, however, are taught in both languages.

Shuang Wen is housed in a corner space in Public School 134, at East Broadway and Grand Street, and blacks are not the only non-Chinese among its 245 students. But the 23 black students are by far the largest non-Chinese group, outnumbering the 11 whites and 8 Hispanics.

As an alternative school, Shuang Wen admits students from all five boroughs, and many of the black children live an hour or more away. There are no school buses serving them, and parents have to drop off and pick up their children.

For Ms. Gamble, a supervisor for the New York City Department of Consumer Affairs, the trip from her family's brick house in Cambria Heights, Queens, starts at 6:45 a.m. Often, her car is stuck in traffic jams.

To the Gambles and other black parents, the sacrifice -- long days for the children and a difficult trip for the adults -- is worth it.

''The long hours and the challenging curriculum are good preparation for the future,'' Mr. Gamble said, ''when they go to college, when they go to graduate school.''

But not all the black parents' friends agree.

''People would ask me, 'Why Chinese? Why not French? Why not Spanish?' '' said Bridgitte Fouche-Channer, another black parent whose daughter is in second grade and whose son is in kindergarten at Shuang Wen. ''I would ask them, 'Why not Chinese?' ''

Sometimes, friends would even accuse the parents of betraying their heritage. Ms. Gamble had a ready answer.

''My children know their heritage,'' she said. ''They know they are African-Americans of West Indian descent. They are not Chinese, nor are they pretending to be Chinese.

''Call me a snob. Call me what you want. I just want my children to have a good, solid education.''

Ruth Smith, a lawyer who had considered sending her daughter to private school, remarked, ''If I had sent my child to a private school, she would be in the minority anyway, since that school would be mostly white.''

The Gambles have decided to send their third child, Patrick, 2, who can already sing ''Happy Birthday'' in Mandarin, to Shuang Wen in two years.

Like many of the black parents of Shuang Wen students, Ms. Gamble, Ms. Fouche-Channer and Ms. Smith are from the West Indies, and that is not a coincidence, they said.

''Shuang Wen reminded us of the kind of schools we know from home,'' said Ms. Fouche-Channer, explaining that schools in Trinidad, Jamaica and the Dominican Republic are often strict and orderly, like Shuang Wen is.

The Chinese parents are generally enthusiastic about the school's ethnic mix.

''The black kids are really nice, and they showed my kids the way when they were new at the school,'' Christine Chuah, who has two children at Shuang Wen, said in Chinese. ''They are seriously interested in learning Chinese, and we like that.''

The teachers, mostly Chinese-Americans or recent immigrants from Taiwan and China, have embraced the non-Asian children as well, offering them extra help with Mandarin.

When Paul Michael, 8, the oldest Gamble child, started at Shuang Wen in second grade last fall, his parents and the school's teachers worried about whether he could catch up with his classmates, who had studied Chinese for two years. But his teacher, Li Ron Wu, had faith in him.

''Ms. Wu said, 'You can do it, Paul Michael. You can do it, Paul Michael. You will do it, Paul Michael.' '' Ms. Gamble said. ''And he did it.'' Now, his Chinese is on par with his classmates.

Mrs. Smith, whose daughter, Iliana, 5, is in kindergarten, said that every day, as soon as she gets home, she asks to do her homework. Ms. Gamble said her children even ask to go to school on days when they are sick. Ms. Fouche-Channer said her daughter, Addis, a second grader, reads beyond her bedtime frequently.

''They love their school,'' said Ms. Fouche-Channer, whose younger child, Makonnen, is in kindergarten at Shuang Wen. ''That's the only way to describe it.''

With its academic success, Shuang Wen has become a desirable alternative not only to neighborhood public schools, but also, for some parents, to the city's elite private schools.

Lydell Carter, a senior program officer with New Visions for Public Schools, an organization that has financed some of the city's alternative schools, including Shuang Wen, is a firm believer in early bilingual education. He transferred his son, Jelani, into the school's fourth grade from Friends Seminary, a well-known private school.

Non-Asian children who started at Shuang Wen in the early grades appear to speak Mandarin as well as children of Chinese descent do, frequently without any trace of an American accent. And in classrooms, in the dining hall and on the playground, the non-Asian students and their immigrant classmates mingle easily, holding hands, arguing with and teasing one another, seemingly unaware of their racial difference.

And a few black and Chinese families have become close. Joshua Foote, a black third grader, regularly calls Jennifer Shyue and her parents for help with Chinese homework, and the families sent the two children to a Chinese camp in Poughkeepsie, N.Y., last summer.

Occasionally, however, some Chinese children will flaunt their higher marks in Mandarin tests to their non-Asian peers. Some black parents have also complained that the school did not take note of Black History Month.

But Gabrielle Gamble, a first grader, sees all the children at the school as her friends, regardless of their ethnic backgrounds.

At school one day, her teacher assigned her to be a buddy and guide for Linda Lin, a shy new classmate from Fujian Province in China.

In the lunchroom, Gabrielle tried to shield Linda from the rambunctious boys while keeping her company.

''What do you like to do?'' Gabrielle asked, earnestly, in Mandarin.

Linda, who was blushing, shook her head.

''Do you like food? Do you like toys?'' Gabrielle asked, again, in Mandarin.

Again, Linda simply stared at her.

Gabrielle looked away, sighed, and concluded, in English, ''She doesn't like talking. But I will keep talking to her.''

By the end of the day, Linda still wasn't talking. But, at least, she was smiling back at Gabrielle.