Sexual harassment in middle and high schools and inequities between boys and girls in the classroom and at home were some issues hashed out yesterday at a conference bringing educators from across the nation to Baltimore County. "Girls are left to feel muted, invisible," said Judy Mann, keynote speaker at the conference on "Gender in a Coed World: Issues for Schools and Families" at Park School. "They're not taught to take risks," said Ms. Mann, a Washington Post columnist and author of the book, "The Difference: Growing Up Female in America." "They are thought to be nice, and they are silenced. We're never going to change the outcome for girls unless we change the way we raise boys." That theme came up repeatedly as workshop facilitators pointed out how boys are allowed to do things in schools and homes that girls are not. In a suburban Massachusetts school, boys got away with running naked outdoors with paper bags over their heads around graduation time, but girls were admonished when they did the same thing, Nan D. Stein told a group of about 50 students who attended her workshop, "Flirting or Hurting? Student-to-student Sexual Harassment in Schools." "When guys act raunchy, it's normal," said Dr. Stein, a senior research associate who directs projects on sexual harassment in schools at the Center for Research on Women at Wellesley College. "When girls do it, they're acting not like girls, and they get in trouble." She encouraged students to list and discuss experiences of sexual harassment. Some brought up lewd remarks, animal noises and sexually suggestive language as examples. But some students could not connect the behavior with "sexual harassment," and defended it as play. One student said Dr. Stein presented the material in a condescending manner, without recognizing that the information was not entirely relevant at Park School, where many of the 775 students have grown up together since kindergarten. The three-day conference drew about 600 educators from 20 states, and 340 students from New York, Maryland and Pennsylvania -- 210 of them Park School pupils. The family-like environment at Park School leaves little room for the sexual harassment Dr. Stein discussed, said the female student, a junior from Mount Washington who did not want to be named. "No one has that obnoxious, bullying sexual harassment attitude . . . This school's very sheltered." Other students identified better with a workshop on "Our Bodies and How They Express Us," moderated by Wendy Salkind of the University of Maryland Baltimore County. In an exercise on the stage of the school theater, she asked students to sit "in a lady-like way." Boys clenched their legs, and some girls appeared to shrink in their seats. When she said they could let go, there was an audible sigh of relief. "It just limits us," Dr. Salkind said of the posture. "It denies us our humanity and really expressing our selves." After the workshop, Thibault Manekin, 17, a junior from Lutherville, said, "It's not a comfortable position at all. I think the male stance is much more relaxed." He said he appreciated the opportunity for his classmates to "talk about gender and sex and stuff like that." Kayla Silber, 14, a freshman from Pikesville, said she learned something about herself. "I found out that I really don't express myself as much as I like to. I withdraw my feelings." Officials at Park began planning the conference 18 months ago at the suggestion of Susan Gauvey, mother of three girls who attend the independent school. "She thought it would be interesting to collaborate and host a conference with gender issues," said Barbara Hoyt, conference chairwoman and school administrator who coordinated the program with the involvement of staff members, student volunteers and $80,000 in foundation grants. "We were fertile ground for this idea." The conference concludes today, with more than 40 workshops on a gender-related topics from 9 a.m. to 3:40 p.m. Admission is $45. The school is on Old Court Road in Brooklandville.