There's no word on what the mystery illness was at St. Thomas More Catholic school, but six students and two adults complained of flu-like symptoms.
None of the reported illnesses are believed to be serious and the school is expected to reopen Friday.
Emmy Milne of the Toronto District School Board says paramedics were called when one student fell ill.
That student was taken to hospital and the others were assessed on the scene.
Milne says the school will be cleaned overnight as a precaution.
Police say the fire department tested the air quality in the school and they haven't found anything out of the ordinary.