Junior
Junior is the CAAO division associated with the IOAA Junior pathway.
Participate
How to Participate
CAAO 2027 — tentative timing
CAAO 2027 is tentatively planned for mid-March 2027. The examination will be online and completed in one day. The exact examination date and registration dates are not yet confirmed. Registration instructions, the fee, start time, writing duration, supervision, permitted resources and submission instructions will be published here when available.
Participation enquiries
For questions about participation, contact info@caao.ca. A message to info@caao.ca is a question, not a registration.
Examination format
CAAO is a one-day online examination, usually held in mid-March. Earlier editions used a week-long format.
Selection
Online CAAO examination
Students write the national examination online in one day, usually in mid-March.
In-person training camp
The top 20–25 students are invited to an in-person camp with several days of training.
TST at the end of camp
Camp participants take the Team Selection Test (TST) at the end of the in-person training camp.
Medals and Team Canada selection
TST results determine medal awards and the selection of Team Canada. Students selected for international representation must also meet the relevant eligibility requirements.
Summer training
Selected Team Canada members continue training during the summer to prepare for IOAA.
Eligibility and divisions
Students may write CAAO for experience even if they do not meet the eligibility requirements for international representation. Selection to represent Canada at IOAA Junior or IOAA is a separate process and requires meeting the applicable eligibility and selection criteria.
Junior and Senior are the two CAAO divisions. Use the past papers for the division you plan to enter.
Senior
Senior is the CAAO division associated with the main IOAA pathway.
What to study
Start with the CAAO Tutorial by Armin Hodaei, 2025. The study guide maps its chapters and lists further reading.
International team eligibility — 2026 reference
These are international age and school-completion requirements for 2026. They are not restrictions on writing CAAO for experience, and they are not the complete team-selection criteria. They do not set confirmed 2027 requirements.
IOAA Junior 2026
- Born on or after July 1, 2010.
- The 2026 host regulations also specify expected high-school completion in 2029 or later.
- Both conditions apply.
IOAA 2026
- Born on or after July 1, 2006.
- High school must not have been completed before January 1, 2026.
- IOAA has no minimum age or grade requirement.
International preparation
Syllabi and past international problems are listed with the study guide.