Firefighters were called to tackle a blaze at the former Buckhaven High School last night (Sunday).
Six fire appliances attended the incident, which was reported just after 9pm.
A height appliance also had to be called out because the fire was on the third floor of the building.
Fire fighters remained on the scene for most of the evening, with the last appliance leaving around 1am this morning (Monday).
Damage to the building was clear from Methilhaven Road this morning, with a lot of smoke damage and a number of windows broken.
However, pupils returned to school at the new nearby Levenmouth Academy as normal this morning.
Stephen Thomson, station manager at Methil Fire Station, encouraged local families to consider the dangers posed by the building, which is in the process of being demolished.
He said: “There are a number of hazards presented by this demolition site, including asbestos, holes in floors, and a number of sharp objects.
“I would ask that parents encourage their children to stay well.”