The Evening Telegraph reports that a pupil of the teacher at a high school in Dundee discovered the explicit material then redistributed it across social media.
It is thought the x-rated photos and footage of the teacher were freely available on at least two pornographic websites.
After the incident surfaced over the weekend, the teacher in question turned up to work on Monday as normal.
However, it is expected that the teacher would face an interview with Dundee City Council education bosses.
The city’s local authority say they are aware of the issue but was unable to comment in detail.
A Dundee City Council spokesperson commented: “It would not be appropriate to discuss an ongoing police investigation.
“The council does not comment on personnel issues.”
Police have confirmed that they are aware of the issue and have launched an investigation.
A spokesman for Police Scotland said: “We are aware of the matter and are making relevant enquiries”.