In Ontario, children must attend school by law from age 6 until they turn 18. Starting in September 2026, high school attendance and class participation explicitly count toward final grades (15% for Grades 9–10 and 10% for Grades 11–12), with penalties applied for unexcused absences.

Legal Attendance Rules

Compulsory Age: Children must be in school from the age of 6 until their 18th birthday, unless they have graduated.
Excused Absences: Valid reasons to miss school include illness, medical needs, or approved religious holidays.
Truancy: Parents can face legal penalties, fines up to $1,000, or probation if a child of compulsory age skips school repeatedly without an excuse. Habitual absenteeism (missing over 40 days) can also trigger formal reporting protocols by school principals. 

Grade Impact (New Policy)

Grades 9 and 10: Attendance and class participation make up 15% of the final course mark.
Grades 11 and 12: Attendance and class participation make up 10% of the final course mark.
Unexcused Absences: Having more than two unexcused absences can prevent a student from earning these full participation and attendance marks.

Reporting an Absence

Parent Action: Parents or guardians must notify the local school office (via phone call or digital portal) with a valid reason before the morning attendance cut-off time. 
Unverified Status: If no reason is given, the absence is marked as unexcused or unexplained, which may affect academic standing under the updated grade guidelines.