NEW LESSONS FOR BOYS, GIRLS IN CALIFORNIA; CLASSES DIVIDE UP BY GENDER.

Byline: Tamar Lewin The New York Times

While New York City's only public school for girls, now in its second year, struggles to fend off a legal challenge, the state of California has begun the nation's most ambitious experiment in single-sex education, a pilot program encouraging school districts to make separate but equal boys and girls ``academies'' an option for middle and high school students.

At the Marina Middle School here, many students who chose the six sex-segregated classes said their parents convinced them that they would do better away from the distractions of the opposite sex. But even if the impetus came from their parents, boys and girls alike said the single-sex classes have let them feel safer about voicing their opinions, and their uncertainties.

``It's more comfortable this way,'' said Eloise Ayala, a sixth-grader, after her class discussed ancient ideas of female beauty. ``Boys are loud, and they get all the attention.''

Down the hall, where the boys' sixth-grade class worked on math problems in small groups, the atmosphere was calm. ``This way, without girls, it's easier to do your work,'' Zaid Assaf said. ``There aren't kids pushing you, saying, `You like her' and `Look at that.' ''

Under legislation passed last year, California offers $500,000 each to districts that create all-boy and all-girl academies with equal facilities, and arrange for an outside evaluation of their pilot program. Six districts made formal proposals, and three have been approved so far, including the program here. The three others are expected to be approved shortly. To some extent, the pilot program only formalizes what was already going on in California - and, to a lesser extent, elsewhere - as schools experiment with single-sex education:

In East Palo Alto, in a hardscrabble neighborhood, the 49ers Academy is in its second year, even though its proposal has yet to be formally accepted by the state. Last year, the academy was an experimental middle school for at-risk boys, providing support services like counseling and visits from members of the San Francisco 49ers football team, one of the school's sponsors. This year, thanks to both the governor's program and legal concerns about excluding girls, there is a girls academy, too, although so far, the boys school has twice as many students as the girls school.

The boys said they learn better. ``Boys sit down and talk for a couple minutes, then pay attention,'' said Michael Ardoin, an 11-year-old. ``If boys and girls are together, they keep talking and interrupting. Girls get you in trouble and make fun of you if you get the answer wrong.''

``It's better with just boys,'' Samuel Gutierrez said. ``You don't get as nervous about girls pointing and saying, `Ha, ha, he got it wrong.' ''

In Ventura, middle school and high school girls' math classes began in 1994, created largely by Pam Belitski, now teaching her fourth year of girls math at Anacapa Middle School. Belitski said the classes were immediately successful with the girls, who spent much of their time making sure that everyone in the class could keep up.

In 1996, after the U.S. Education Department's Office for Civil Rights intervened, the classes were opened to boys, but Belitski said only one boy signed up, as a joke, and he transferred out after a few days.

In San Francisco last year, Marina Middle School created one seventh-grade class of boys and another of girls, with a math-science teacher and a language-social studies teacher swapping classes at lunchtime.

In an informal end-of-year survey, all the girls but one said they liked it and would do it again, and about half the boys said they would do it again, although almost all the boys said their grades were better. This year, with the new state money, the program became a school within a school for all three grades. The girls say they liked not having to worry about how they looked or sounded to boys, or having to compete with them for attention. The classes have attracted some Islamic girls, in head scarves, whose parents wanted to keep them from too much mingling with boys.

Although single-sex education is hardly a new idea, its resurgence in public schools poses thorny questions for lawyers, educators and policy experts alike.

Legally, single-sex education is still on shaky ground: in response to a complaint from civil liberties groups, the Office for Civil Rights has warned New York City that its failure to offer boys a facility like the Young Women's Leadership School in East Harlem violates Title IX, the federal law prohibiting sex discrimination in schools that receive federal money.

While there has been no definitive legal ruling on whether ``separate but equal'' is acceptable for gender - as it is not for race - the Office for Civil Rights has said single-sex schools are an acceptable way to diversify educational choices as long as a district offers boys and girls the same classes and the same resources, as California is doing.

In New York, though, schools Chancellor Rudy Crew has said he will not create a boys school to balance the East Harlem girls school. Rather, he portrays the school as an an effort to remedy educational practices that leave girls behind, especially in math and science.

In contrast, Gov. Pete Wilson, the driving force behind the single-sex schools in California, where government affirmative action programs have been outlawed, talks about them only as an expansion of school choice, a way to offer parents more public school options.

But even if California's single-sex academies comply with antidiscrimination laws, they may well face legal challenges on other grounds, like the constitutional guarantee of equal protection.