The choices change as they grow - 8-year-olds watch more TV and 17-year olds listen to more music on CDs, radio, and tapes. It doesn't make much difference since they remember next to nothing of what happens on the tube or the CD unless it's violent or raunchy.

Most plug in to more than one source at a time. Some do multi-tasking on e-mail, TV and phone while working a word processor on homework at the same time.

With this schedule, there's no time left for family and recreational activities leaving little doubt as to why today's kids are more depressed and 10 to 20 pounds heavier than the kids of the 70s.

The Kaiser Family Foundation conducts ongoing surveys of the activities of children and teens and also asks hundreds of children to keep seven-day diaries of their media use.

Since 1999, time on computers and video games has doubled while TV has increased only a little - probably because the maximum is near. Sixty percent of those between 8 and 18 have the TV on during meals, and 51 percent of families have the tube on all the time whether anyone is watching or not.

Teenagers often have TVs in their bedrooms (68 percent) and usually have a VCR, DVD or video game player as well (50 percent). Also 20 percent have premium TV channels and 20 percent have internet access in their rooms.

What can parents do? They should know what their children are watching and set down rules. The rules should put limits on the violent and sexual content. Only 20 percent of 7th to 12th graders report that their parents enforce rules. They must be right because only six percent of parents use V-chip screening to restrict TV content and only 10 percent check parental advisories on music or video game ratings.

Nearly half of the under-18 set have gone to an R-rated movie without parent permission. And 65 percent have played Grand Theft Auto - that controversial game of crime and violence (beating up prostitutes and killing police officers).

The amount of violence on television overwhelms even the most grown-up teenager. On premium cable, 85 percent of the shows have violent story themes. On basic cable, the story theme has to do with violence 59 percent of the time. Independent networks come in at 44 percent, while PBS is at 18 percent.

Hobbies, crafts, and sports all give a child or teen a chance to learn new skills and develop pride in his abilities instead of envying the bad habits of TV characters. Invest in good age-appropriate reading materials and, of course, insist on schoolwork before entertainment.

The argument that media violence is reality is just not true. Violent TV scenes leave out long-term consequences 84 percent of the time, while 58 percent show no pain and 47 percent show no harm to the victims. Perpetrators go unpunished 73 percent of the time.

The message is too dangerous to ignore. Enforce your rules.