Let's be honest, even today, school shootings are statistically insignificant by almost any measure- be it total deaths, total homicides, total shootings, or even total deaths by firearm. In no category does it make up even a fraction of a percent. However, as to Big Tex's comment- look at how many school shootings we've had in the last twenty years and compare them to earlier times when there was far less gun control.
I think what everyones missing is we need more media control. These things are happening more frequently now IMO because kids see and hear about them now. They want their 5 minutes of fame.