The content is said to be causing “extreme distress” to teachers.
Students in Northern Ireland have been warned to be vigilant against TikTok videos in which pupils rate their teachers, the BBC reports.
The PSNI have said that some of the content circulating is abusive, and may even be classified as criminal.
In a statement, Justin McCamphill from the NASUWT teachers’ union said that the videos are causing “extreme distress” to the teachers affected, many of whom have had to take sick leave. He also called for parents to be aware of their children’s online activity.
Mr McCamphill said: “We are calling on school principals and governors to co-operate with the PSNI to ensure this activity can be properly investigated.
“We warn parents and pupils that they need to be aware of the consequences of this.”
He added that while all the content was “uncomfortable” for teachers, many of it was “clearly criminal content”.
The PSNI meanwhile said: “While those involved may not see the harm in their actions, they are causing real distress to the individuals targeted.”
A spokesperson for TikTok said that the platform removes any content which violates their community guidelines.
The statement read: “Our community guidelines make clear that we do not allow accounts that impersonate people in a deceptive manner, nor do we tolerate content that contains bullying or harassment, statements targeting an individual, or hateful speech or behaviour.
“We remove any content that violates these guidelines.”
The Department of Education pointed to the Safer Schools NI app, which aims to increase protections for teachers, students and their parents and carers.
A spokeswoman for the department said: “The issue of safeguarding and child protection is a key priority for the minister.
“The Safer Schools NI app launched today is a further example of the importance of access to proper safeguarding resources for teachers, parents/carers, children and young people.
“The app supplements the safeguarding and child protection support already provided to schools by giving up-to-date advice and support on topical issues from safeguarding experts.”