St. Mary Catholic Secondary School is a Catholic secondary school located in Pickering, Ontario, Canada established in 1987.

On March 22, 2012, approximately 200 to 300 students were sent home due to wearing either shorts, khakis, capris and/or ankle socks, sparking outrage amongst students and parents.

It was then brought to light that a black man's quote was changed from him commemorating his grandma and thanking her for her support of his years of high school, to a racist message.

This made the school issue a return on all yearbooks and announcing an investigation on the people who had changed his quote.

The nine people were a mix of male and female students from various cultural backgrounds.