Police have become involved after reports schoolmates of a Down syndrome girl posted videos online of her flashing her breasts and licking the ground.
The Wellington East Girl's College student, 15, was bullied by a group of girls who pretended to be her friend then encouraged her to do the demeaning acts, Fairfax reported.
The group shared footage of the girl on Facebook and Snapchat, captioning it with "slag" and "yummy".
Principal Sally Haughton sent an email to parents saying the school had been working with police from early on, Fairfax reported.
"We are involved in an investigation related to the taking and circulation of images of a Wellington East Girls' College student on social media," her email said.