École secondaire publique Mille-Iles (Thousand Islands Public High School) was founded in 1994. It was initially started as a French program within Kingston Collegiate and Vocational Institute (KCVI) in 1977. In 1980 this became a separate module, serving students in grades 9 to OAC. The establishment of a distinct francophone public high school was first suggested in 1987, and the project came to fruition in 1994, leading to the inauguration of Mille-Iles as a distinct entity in 1995, still within the KCVI building. The school moved to its present location (the former location of Calvin Park Public School) in 1999, when it also expanded to welcome students in grades 7 and 8.