Two teenage girls from a Stockholm school have been fined 2000 kroners (A$300) each after being nabbed for bugging their teachers' meeting room.
Their operation was exposed after one of the conspirators revealed on Facebook that they had planted a listening device in the school's staff room.
The girls were after an inside scoop on upcoming exams and hoped to discover how their teachers viewed them, according to Swedish newspaper, The Metro.
The girls hatched the plan after finding the teachers' meeting room empty when they were returning a set of lost keys.
They bought the listening device from a local tech store, returned to the school, waited for the janitor to leave and planted the device.
The girls had executed the plan the night prior to a teachers' meeting where they knew the exams would be discussed.
However, a few hours after the successful installation, one of the conspirators could not "keep quiet", exposing their escapade on Facebook.