CentrX says:
fifteen students were killed by guns, according to the Centers for Disease Control and Prevention. By comparison, fifteen high school football players died during regular season and playoff games in 1999
Actually, 15 deaths per year is a pretty high homicide rate considerning that this is happening at schools.  In the age group of 15-19 in the United States, accident is the leading cause of death, followed by homicide.  Of which, 82% of homicide involves firearms!  If homicide rate is just as high as accidental death rate, I would be very worried.

1998 United States
Ages 15-19, All Races, Both Sexes

National Center for Injury Prevention and Control (http://webapp.cdc.gov/)

Unintentional Injuries and Adverse Effects
MV Traffic                         5,060   76.8%
not MV traffic related             1,530   23.2%
Total Deaths                       6,590
Homicide and Legal Intervention
Firearm                            1,898   82.1%
not firearm related                  413   17.9%
Total Deaths                       2,311
Death by firearms is a greater cause of death than non-MV related accidental injuries.

Statistics aside, homicide is intentional and malicious.  These are kids who can't even legally consent, lurking around in schools with guns, never mind if they have a license or not.  I haven't heard of any murderer use the self defense plea after school shootings.  The proliferation and easy access to firearms is alarming, and that's why the papers are selling.