Talking on the phone is so old school. Most teens today prefer texting. About 75 percent of 12- to 17-year-olds in the United States own cellphones, and 75 percent of these teens send text messages, according to the Pew Research Center's Pew 2010 Internet and American Life Project.

Teenagers strive to fit in with their peers as they begin to spend less of their free time with their families and more of it engaged in activities with friends. Peer pressure can have negative and positive effects on teenagers. Teens may aspire to get good grades and join a club that a peer whom they admire leads.