ASHLAND, Mass. - Along with corsages and rented limos, prom season evokes grimmer images for many Massachusetts students: a bloodstained dress, and the tale of a girl's relationship with a murderously abusive boyfriend.
As part of a statewide effort to combat teen dating violence, thousands of students at dozens of high schools have seen ''The Yellow Dress,'' a play based on real events, set on the eve of a prom. Only in the final act does the heroine reveal she was battered to death the previous day.
While few states approach the scope of Massachusetts' program, many school districts nationwide are treating dating violence with increasing seriousness.
The Centers for Disease Control and Prevention estimates that 22 percent of high school students have been victims, with girls usually the target in the most serious cases.
''We need to find ways for our young women to be equals in relationships,'' said Gail Gauthier, the health coordinator at Ashland High School. She organized showings of ''The Yellow Dress'' last week for ninth- and 10th-graders.
Dating violence isn't new. Boyfriends and girlfriends have been insulting and slapping each other since high school romances began. But experts detect some worrisome trends: possessive dating behavior extending into ever-younger ages, and surveys suggesting many teens think some degree of dating violence is acceptable.
''The problem is probably a bit more prevalent than it was decades ago,'' said Rebecca Yarmuth, who oversees dating-violence programs for the Seattle community agency New Beginnings. ''But the biggest change is the awareness of it and the reporting of it. Because it involved younger people, it used to be discounted as puppy love.''
Many adults still underestimate the dangers, according to Carole Sousa, a consultant to the Massachusetts Department of Education. She notes that domestic violence laws in most states are tailored toward adult relationships and fail to account for the special problems of teen-age victims.
''As a society, we're not getting kids the message that we're taking it seriously,'' she said.
At Ashland High, a school of 600 students 30 miles west of Boston, administrators have been taking the issue seriously for several years. Dating violence is addressed in the health curriculum, and almost every student has seen ''The Yellow Dress.''
The play is taken to schools throughout Massachusetts and sometimes other states by Deana's Fund, founded by the family and friends of Deana Brisebois. The young woman from Topsfield, Mass., died in a car crash in 1994; the driver, unscathed, was her abusive boyfriend.
The play's heroine, Cindy, recounts her fictional boyfriend's gradual progression from tenderness to controlling abusiveness, mocking her in public, isolating her from her friends, pressuring her to have sex, bruising her with blows.
''How could a guy who said he loved me do this?'' asks Cindy.
In a group discussion afterward, sophomore Andy Talvey said many students feel intense pressure to date, to the extent that his classmates already worry about finding a partner for the junior prom a year from now.
Kris Hanrahan, another sophomore, said she understands why some girls put up with abuse.
''Once you get into a relationship, there's pressure to stay in it,'' she said. ''When you break up, your whole social life falls apart.''
Introducing the play, Gauthier stressed to the 10th-grade boys that they should not feel persecuted.
''This is not male-bashing,'' she said. ''I don't believe males are genetically abusive.''
But she said 95 percent of serious dating-violence incidents are male-against-female, and told the boys they should find ways to be caring without losing self-confidence.
Junior Nicole Brogan recalled getting goose bumps watching ''The Yellow Dress'' in 1998. She said boys in her class - despite some bluster - also were moved.
''People can go in looking at it as a joke,'' she said. ''But I think it leaves a lasting impression on them, even if they might not express it.''
In the group discussion, police officer Pam Atwood said she has investigated some dating incidents where the victim was male, including one brawny college student who curled up in a ball while his petite girlfriend punched him.
Some studies have suggested that almost as many boys as girls are victims of dating violence, but Sousa contends such figures are misleading. Boys may be mocked or slapped by a girlfriend, but they often laugh off the mistreatment, she said. Girls almost exclusively are the victims in cases of sexual violence or injuries requiring hospitalization, Sousa said.
Emily Rothman, director of batterer intervention for the Massachusetts Department of Public Health, said some adults are uneasy about the initiatives to curb dating violence.
''In a lot of cases, adults don't want to think of children having romantic lives and sex lives,'' she said. ''To address the fact that they're having unhealthy relationships, you have to accept that they are having relationships in the first place.''
On the Net:
CDC's Division of Violence Prevention: http://www.cdc.gov/ncipc/dvp/yvpt/datviol.htm