The simple explanation for school shootings is an acceptance of the fact that advertising works. Every sensational school shooting story, repeated over weeks in every venue sets up the next sick mind to prepare for the next atrocity. The simple question is “where did the shooters learn to do school shootings?” From their parents, at school, in church where did they learn to do this? Which came first, the chicken or the egg? The cycle of school violence has become a media driven event. An easy first step might be to ban the use of the murderers name after the first 24 hours and another step would to be very careful of the unending, often excusing analysis of why the shooting occurred in the media, as I believe some individuals will seize on that faulty analysis and use their own faulty analysis of their own experiences to legitimize a future heinous act in their own part
I also find it interesting that, if you overlay the data you find that most mass shootings take place in areas that have relatively lower per capita gun ownership. Perhaps if we answer that particular, “why” question we may have a foundation for further progress in curbing all gun violence.