GCI is one of the oldest continually operating high schools in the province of Ontario. Tassie Hall is named for the school’s first principal. Dr. William Tassie was principal until 1881. The GCI mascot is a ghost! A former custodian, David MacGeorge worked and lived at GCI for 40 years and was a published poet. GCI celebrated its 150th anniversary in 2002. Every year, one or two alumni are inducted into GCI’s “Stairway of Excellence”.