"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."

"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.

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.