Joseph Kett who surveyed the history of youth in the U.S. in Rites of Passage has spoken and written quite about the issue of school violence (not spree killings in general). Basically, taking the long view, Kett shows how schools were pretty violence places in the past. One of the reasons for age grading was that the violence of teen males was said to be better controlled by grading them off from younger boys. He quotes liberally from Horace Mann, an educator in the 1800s, who wrote about student violence against teachers. He tells stories of violent disruptions, torture of teachers, outbursts and uprisings, etc. There was resistance to women as teachers for a long time because people didn't think women could handle it.
There were also shootings in the past. The one I know about from Kett is that, in 1840, a student killed a professor with a muzzle loader at University of Virginia. It got brought up a lot after the shootings at Virginia Tech.
shag