By PATRICIA LEIGH BROWN
 
CHULA VISTA, Calif., April 17 - At home with his family - four brothers and a foster mother - Jorge Geraldo struggles with pimples and shyness, a handsome 18-year-old with deep brown eyes who sleeps on Goofy and Donald Duck sheets that tend to lie in an unmade heap on his bunk bed.

But come the weekend, he dons his traje de charro - the suit of the horseman, a glimmering costume with gold buttons slithering up the sides and custom-fitted by a tailor in nearby Tijuana - to become the lead singer in Mariachi Chula Vista, a group of high school mariachi musicians who have forsaken John Philip Sousa marches at halftime of football games in favor of spending the weekends playing at parties, baptism receptions and the like.

The 15 young musicians - cellphones attached to elaborately stitched leather belts to communicate with carpooling mariachi moms and dads - are stars in a spirited and growing movement to bring the centuries-old Mexican musical tradition of mariachi to public schools.

Across the country, more than 500 public schools now offer mariachi as part of the curriculum, said Daniel Sheehy, a mariachi expert and director of Smithsonian Folkways Recordings in Washington.

Mariachi music is aggressive and festive, dominated by a celebratory explosion of trumpets - usually played in short, fast bursts - lilting native vihuela and guitarrón guitars, and occasionally punctuated by a grito, which is jubilant, soulful yell.

The music is flourishing in San Antonio, where a high school mariachi class has been offered since 1970, and at Chula Vista High School here, six miles north of the border with Mexico and where the student body is 78 percent Hispanic. But mariachi has also taken root in Milwaukee, Chicago, Tucson and Albuquerque, and in small towns with large migrant populations like Wenatchee, in eastern Washington.

Two years ago, the Clark County School District in Las Vegas recruited Javier Trujillo, a 28-year-old musician from Tucson, to develop a mariachi curriculum at 10 schools. He has hired eight teachers, with five more en route - so many that the teachers recently formed their own mariachi ensemble.

The mariachi movement has also crossed cultures. At the Oak Grove Middle School in Concord, a San Francisco suburb, the student population is 67 percent Hispanic, and mariachi is taught by Emile Patton, who is half African-American. One of her lead singers is Connie Kakhigna, a seventh grader whose parents are Laotian and Vietnamese.

"It's a different culture than mine, so to learn it is cool," she said. "Most of my friends are Hispanic. This makes me feel involved with them."

The number of students involved in mariachi is "growing substantially," said John Mahlman, the executive director of MENC, formerly the Music Educators National Conference, in Virginia. Mr. Mahlman said his organization was conducting a nationwide survey to see how far the trend had spread.

"It's a musical bridge between family, school, community and culture," he said.

As a middle school student, Mr. Geraldo, who is now a high school senior, spent a brief stint playing Sousa marches and Bruce Springsteen medleys on the trombone as a member of the marching band. "I tried to relate, but it was really weird," he said. "It's hard being Mexican in America, because society says you have to adjust to succeed."

Then he discovered mariachi, developing calluses to play the guitarrón, a six-string bass, his voice perfectly suited for Romeo-like songs of temptresses and betrayed love. "Something took over me," he recalled. "I felt alive, I guess. It was like, 'Wow.' I didn't know you could do that with music."

Texas and California, a state in which Hispanics are expected to be the majority by 2040, are in the forefront of the mariachi-in-the-schools movement. The music is joining band, orchestra and choir in the school music pantheon.

The members of Mariachi Chula Vista - the sons of construction workers, nurses aides, and truck drivers, and the daughters of welders, mechanics and supermarket clerks - are the most accomplished group in the Sweetwater Union High School District, one of the nation's fastest-growing school districts and a highly evolved mariachi outpost: 12 of 20 junior high and high schools now offer classes.

The Mariachi Scholarship Foundation provides $750 college stipends for graduating seniors and varsity letters are awarded for mariachi performance. The first Chula Vista International Mariachi Conference is to take place this June.

The members of Mariachi Chula Vista, accompanied by Mark Fogelquist, a 57-year-old teacher who plays the violin and has a master's degree in ethnomusicology from the University of California, Los Angeles, are in demand on weekends. They have played at birthday parties, weddings, housewarming parties, the opening of a department store, a post office retirement party and who knows how many baptisms.

One of the baptisms was for baby Antonio Serrano, held in a park with a view of Tijuana that was transformed by the sheer joy of the music into a mini-Plaza Garibaldi, the fabled mariachi gathering spot in Mexico City. Staccato trumpets and violins in lush three-part harmonies filled the air, mingling with the smell of gorditas on the grill.

The proceeds - as much as $1,800 on a busy weekend - help pay for a tailor, who crosses the border to measure for costumes, and trips to festivals like the Tucson International Mariachi Conference, where students study with maestros like Victor Cardenas of Mariachi Vargas, who autographed a vihuela guitar for 16-year-old Martha Ramirez. For many, "it is their first time staying in a hotel, or flying in an airplane, or meeting people from another social strata," Mr. Fogelquist said.

"You don't see the marching band and the choir playing four gigs a weekend," he added. "Mariachi is part of the musical life of the culture, a part of the daily life of Mexicans in a way that's hard for Americans to understand."

In Chula Vista, where Interstate 805 separates older neighborhoods mired in poverty from new subdivisions with walking trails and three-car garages, mariachi music is helping students to cross an even more profound divide.

Nationally, Hispanic students lag behind both white and African-American students, with 10 percent earning college degrees, compared with 34 percent for whites and 18 percent for blacks. Hispanics also drop out of high school at a higher rate - 25 percent, compared with 13 percent for blacks and 7 percent for whites.

Edward M. Brand, the Sweetwater superintendent, said that the mariachi program, which started as an after-school class in 1996, and literacy and other arts programs have helped keep Hispanic students in school. Ten years ago, he said, the dropout rate among the district's Hispanic students was 20 percent; today, it is just under 6 percent.

Mr. Fogelquist watches over his students - from arranging rides for musicians whose parents do not have cars to making sure that one of his students who is struggling with math remembers to sit in the front row of the math class.

"He wants us to respect ourselves," said Mr. Geraldo, who plans to enter college next year. "That's the whole deal."

Mariachi was the music of itinerant rural musicians, an adaptation of Spanish theatrical music incorporating violins, harps and guitars. Its popularity has been somewhat eclipsed in Mexico, where it is considered "something of the past that you experience at weddings or baptisms or in bars when you're drunk," said Hugo Morales, a MacArthur fellow and the founder of Radio Bilingüe, the Latino public radio network, which sponsors a mariachi conference in Fresno.

Victor Quezada, 43, the father of Angel, a 16-year-old violinist, grew up in Tijuana listening to Pink Floyd, Deep Purple and Lynrd Skynrd. "When my son first started I said, 'No mariachi! Why not a rock band?' " he recalled.

For recent immigrants and especially for young people, Mr. Morales said, mariachi helps foster cultural identity and self-esteem, helping the young "articulate their feelings through music."

After rehearsals, Jorge Geraldo takes care of his four brothers. At home, said Martha Jimenez, 40, his foster mother, he sings while washing dishes or taking out the garbage, inspiring cousins from near and far. "Kids around here can be influenced in so many directions," she said. "You see him on stage and you know how big a part of him mariachi is."