A cell phone seems as vital as an iPod, MySpace page and video games for U.S. teens. Wireless service providers and accessory suppliers cater eagerly to young users, a rapidly growing market and an especially trend-conscious one. Many also turn into high-volume users, a new study shows.

"Teens simply use their phones to do more, from text messaging to purchasing premium content," explains Frank Dickson of MultiMedia Intelligence, a business research firm. Its national survey of more than 2,000 teens, released last month as a 35-page report, says more than 16 million Americans aged 12-17 have their own cell phones -- up 12 percent from 2006. "The teen market has been the 'golden child' for cellular providers in the U.S.," says Dickson, noting that 57 percent of teens have cell phones by age 13.
As a bonus for the industry, teens often teach parents how to use service upgrades -- increasing cell use, and bills, for the whole family.

Even schools recognize the educational value of handsets with Internet access, though many districts require them to be kept in lockers or turned off during class hours. New York City offers teachers classes on how to incorporate cell phones into lesson plans. Suggested readings include an essay titled, "What Can You Learn From A Cell Phone? - Almost Anything!"

Gender gap: Of all teens, 17-year-old girls are the most likely to carry cell phones. Ninety-one percent of them had handsets last year, compared with 78 percent of 17-year-old boys.

Road risk: North Carolina drivers under 18 are prohibited from using a cell phone, even with a headset, while behind the wheel. The state law is widely ignored, traffic safety experts say.

Educator says: "We need to keep our schools free from disruption -- free from telephone calls, texting, surfing the Web, taking pictures, playing games -- all the things that cell phones bring into schools. The instructional potential of phones should be explored outside of the classroom." - David Cantor, New York City Department of education spokesman