A police investigation is underway at King William's College in Castletown after a hidden camera was discovered.
College principal Martin Humphreys confirmed officers were called into the school when the digital recording device was found in a toilet area on Wednesday.
A pupil has been suspended and is currently being questioned about the incident, described by Mr Humphreys as 'a very serious matter'.
All parents have been informed.
In a statement, the principal says the priority for College now is 'to reassure the children and their parents and guardians that all proper steps have been taken'.
Charity reports marked increase in level of debt residents are struggling with
Bus drivers' strike: Hopes for new offer as negotiations continue
Charity encourages Manx residents to learn basic sign language
Doctors claim 'critical shortfall' in hospital beds is posing 'direct risk' to life
'Pressure in the system' but bed figures are wrong says Manx Care