Two pupils from Mbilwi Secondary School in Limpopo have been suspended in connection with the assault on Lufuno Mavhunga.
Mavhunga later died in an apparent suicide.
Limpopo education department spokesperson Tidimalo Chuene told News24 on Thursday that a disciplinary hearing had been set for 22 April.
This comes after a 15-year-old was arrested and charged for the assault on Mavhunga.
In a viral video shared on social media, a pupil can be seen repeatedly slapping Mavhunga, who does not retaliate. Other pupils appear to watch and cheer.
An inquest docket has been opened into Mavhunga's death.
According to Limpopo police, it is alleged that, after the incident, Mavhunga came home, locked herself in a room, and consumed a large number of pills.
She was rushed to hospital and declared dead on arrival.
Meanwhile, Jacaranda FM reported that, during a Q&A session with Minister of Basic Education Angie Motshekga during a visit to the school, it emerged that Mavhunga had apparently reported instances of bullying to two teachers, but no action was taken.
Motshekga said she was awaiting a report on the investigation.
* An earlier version of this story stated that three pupils have been suspended, according to information provided by the Limpopo education department. The spokesperson has since confirmed that it was, in fact, two pupils.