NCCI operates on a semestered school year at the upper level (Grades 9-12). Classes normally commence on the last Monday of August and are completed in early June. The first semester begins in late August and the second in mid-January. Senior students choose four courses per semester, eight per year. The school day begins at 8:30 a.m. and last period ends at 3:30 p.m. There are four 78-minute periods per day. Following classes, NCCI's extra-curricular programs begin; they continue until 5:30 p.m., Monday to Thursday.All students have two-week vacations in December and March. During the holiday periods the residence is closed. Families are expected to make suitable arrangements in advance for their child's transportation home; foreign students are expected to establish suitable accommodations with friends or relatives in Southern Ontario. NCCI can assist in arranging alternative accommodations at a reasonable cost.

The Lower School (JK to Grade 8) also begins at 8:30 a.m., with the last class ending at 3:40 p.m.

Final examinations are conducted twice a year in most secondary school subjects. Every student receives effort grades and achievement reports at regular intervals over the course of the school year.