I remember reading about the school explosion in Liberty, TX that killed two hundred or more kids but that was due to a leaky gas line, this before a scent was added to gas and the reason it was. The kids complained about headaches for a week before the tragedy.
The Bath School disaster was a series of violent attacks perpetrated by Andrew Kehoe on May 18, 1927, in Bath Township, Michigan, that killed 38 elementary school children and six adults and injured and least 58 other people.