Bells segmented the school day into periods in Gary, Indiana, a steel town.
Bells had been part of schools long before the industrial era. Handbells summoned students to one-room schoolhouses throughout the eighteenth century, just as church bells called congregations to worship. The bell was a signal, not a system.1
The transformation came when bells began segmenting the school day into fixed, interchangeable periods. This shift is often traced to William Wirt, who became superintendent of schools in Gary, Indiana, in 1908.2 Gary was a company town built by U.S. Steel, and Wirt designed a platoon system in which students rotated through classrooms, workshops, and playgrounds on a strict schedule, maximizing the use of every room in the building.
The Standard Electric Time Company, founded in Massachusetts in 1884, sold synchronized clock and bell systems to both schools and factories.3 The technology was not designed to imitate the factory floor. Early synchronized bells in schools served primarily as fire alarms. A 1913 report from Insurance Engineering described roughly 250,000 American school buildings as built to burn, with school fires occurring at a rate of approximately ten per week.4
John Taylor Gatto, a former New York City and State Teacher of the Year, became one of the most vocal critics of the bell system, describing schools as prisons of measured time.5 Gatto argued that the bell conditioned students to stop thinking on command and move to the next subject regardless of engagement, a rhythm that mirrored the shift changes of industrial labor. Education historian Audrey Watters has noted, however, that Gatto’s account oversimplifies a more complex history in which bells predated the factory model by centuries.6
John Dewey, who inspected and praised the Gary schools, insisted the system was not designed to produce factory workers but to give children from immigrant families access to a richer education than the traditional model offered.7 The bell that organized Wirt’s platoon schedule now organizes nearly every school system on earth, segmenting learning into uniform blocks that begin and end at the same moment for every student in the building.