Even a teen who knows better than to initiate calls behind the wheel will dive for a vibrating phone. "People are conditioned to pick up when the phone rings," Winston says. There's also pressure from senders to get a reply. "You feel like you have to answer right then and there," says Nicole Meredith, 18, of Louisville, Kentucky. "Everyone wants an instant response." Waiting to reply didn't occur to Meredith in July 2008 as she drove to a sleepover at her best friend's house. When her pal texted wanting to know where she was, Meredith started to text, "I'll be there ... " In those few seconds she crossed the left lane, hit the median and spun out. "Everything was a blur," she says. "I heard the tires screeching and a huge boom." She collided with a barrier that kept her from smashing into oncoming traffic on the opposite side of the highway and was lucky enough to walk away unharmed. Other teens suffer far worse consequences. Amanda Martin, 17, of Southbridge, Massachusetts, was texting several friends on her way to school one morning in 2007 when her car left the road and hit a tree. She died that day. "Coming around a curve, she just sailed off the road," says her mother, Melissa. "There were no skid marks—she never even hit the brakes."