A SCHOOL community is mourning the loss of a high school student who collapsed during class today and died.

A Facebook post from Ormeau Woods State High School informed parents and carers that a student had suffered a "serious medical incident" at school this morning.

"Out of respect for the family, I am unable to provide any other information at this time," the post signed by acting principal Dan Finn said.

Afternoon tutorials were cancelled as students and staff came to terms with the loss of their classmate.

Nine News reported that the boy was 15 years old and fell off his seat in class. A teacher performed CPR and the ambulance service was called, but he could not be revived.

The school said counselling services would be made available for students sturggling to cope with the sudden death.

"Out of respect for the family, I am unable to provide any other information at this time, but rest assured, the well-being of your children and the welfare of our staff is our highest priority at this time."

The matter has been referred to police and no cause of death has been confirmed.