The instant text, picture and video messages have become part of some teens' courtship behavior, police and school officials said. The messages often spread quickly and sometimes find their way to public Web sites.
"I've seen everything from your basic striptease to sexual acts being performed," said Reynoldsburg police Detective Brian Marvin, a member of the FBI Cyber Crime Task Force of Central Ohio. "You name it, they will do it at their home under this perceived anonymity."
Westerville Central High School senior Jerome Ray said he's received such unsolicited messages, including one from a classmate while he was sitting with his girlfriend.
"A lot more girls are aggressive," said Ray, 18. "Some girls are crazy and they are putting themselves out there."
Candice Kelsey, a teacher from California, said some teenage girls think they have to be provocative to get boys' attention. As a result, they will send photos they hope their parents never see.
"This happens a lot," said Kelsey, author of Generation MySpace: Helping Your Teen Survive Online Adolescence. "It crosses every racial socio-economic group. Christian kids are doing it. Jewish kids are doing it."
Male teens are also doing it.
For instance, a central Ohio high school teen made a sexual cell phone video of himself and sent it to female classmates. One of the girls forward the Westerville South High School's video to at least 30 other people.
A study last year found teens are placing more of an emphasis on image and fame than in the past. Jean Twenge, a psychology professor at San Diego State University who studies young people's trends, found that teens are more confident and assertive than ever before.
"Adolescents are not known for thinking things through - that's a generational constant," she said. "Now, with the technology that is out there, instead of taking a picture and passing it around the classroom, it's online, which is a whole different ball game. (Teens) don't see it that way."
Mark Raiff, a principal at Columbus' Olentangy Liberty High School, said some of his students and their cell phones have caused trouble.
"They don't see anything wrong with it," he said. "It leaves me speechless."