The Bath School disaster, also known as the Bath School massacre, was a series of violent attacks perpetrated by Andrew Kehoe on May 18, 1927, in Bath Township, Michigan, United States. The attacks killed 38 elementary schoolchildren and 6 adults, and injured at least 58 other people. Prior to his timed explosives detonating at the Bath Consolidated School building, Kehoe had murdered his wife, Nellie Price Kehoe, and firebombed his farm. Arriving at the site of the school explosion, Kehoe died when he detonated explosives concealed in his truck.

Kehoe, the 55-year-old school board treasurer, was angered by increased taxes and his defeat in the April 5, 1926, election for township clerk. He was thought by locals to have planned his "murderous revenge" after that public defeat. Kehoe had a reputation for difficulty on the school board and in personal dealings. In addition, he was notified in June 1926 that his mortgage was going to be foreclosed upon. For much of the next year until May 1927, Kehoe purchased explosives. He secretly hid them on his property and under the school.

On May 18, 1927, Kehoe then set off almost simultaneous explosions at his farmstead and at the Bath Consolidated School. His devices destroyed the farm's buildings and ripped through the north wing of the Bath Consolidated School building. As rescuers began working at the school, Kehoe drove up to the schoolyard and detonated dynamite inside his shrapnel-filled truck. The truck explosion killed Kehoe plus four other people, and also injured bystanders. During the rescue and recovery efforts, searchers discovered an additional 500 pounds (230 kg) of unexploded dynamite and pyrotol in the south wing of the school that had been set to go off at the same time as the initial explosions in the north wing; Kehoe had apparently intended to destroy the entire school and kill everyone in it.