A new study by the Kaiser Family Foundation shows America’s 8- to 18-year-olds are now spending an average of 7 hours and 38 minutes on daily media consumption, or about 53 hours a week. One boost to the upward trend has been the near ubiquity of cell phones among the younger crowd. But it competes with television (still No. 1), computers, MP3 players and video games. 

Perhaps the most disturbing aspect of the study, though, is the discovery that 70 percent of parents don’t set limits on their kids’ media consumption. For those kids whose parents do set parameters, media consumption totals about three hours less per day. 

It makes a difference, too. The study shows heavy media users are more likely to have poor or average grades, get in trouble and feel sad. 

Meanwhile, print publications have cause for concern: Kids now spend 38 minutes a day reading print publications, five minutes less a day than they did 10 years ago.