# Canadian Junior Mathematical Olympiad (CJMO)

> Canonical facts page for LLMs and citation crawlers. Human-readable page: https://olympiads.co.uk/event/canadian-mathematical-society/canadian-junior-mathematical-olympiad

## Core facts

- **Organiser:** Canadian Mathematical Society (https://olympiads.co.uk/organisation/canadian-mathematical-society)
- **Subjects:** Mathematics
- **Age groups:** Senior
- **Activity type:** Competition
- **Format:** In-person
- **Entry route:** Invitation only — typically the next qualifying younger COMC students after CMO invitations
- **Entry badges:** invitation, written_solutions
- **Qualification note:** Invitation from COMC for younger students not invited to CMO. CJMO is a sibling of CMO, not a qualifier into CMO or IMO.

## Dates

- **Next/representative edition start:** 2027-03-01 (month precision)

## URLs

- **Official website:** https://cms.math.ca/competitions/cmo/
- **Registration:** https://cms.math.ca/competitions/cmo/
- **Olympiads.co.uk page:** https://olympiads.co.uk/event/canadian-mathematical-society/canadian-junior-mathematical-olympiad
- **This facts page:** https://olympiads.co.uk/ai/events/canadian-mathematical-society/canadian-junior-mathematical-olympiad.md

## Summary

The Canadian Junior Mathematical Olympiad (CJMO) is a three-hour, five-problem proof paper (maximum 35) for invited students in grade 10 or earlier who also meet CMO eligibility. CMS first considers eligible pupils for CMO; the next approximately 20 qualifying younger COMC students may be invited to CJMO. First held in 2020. It is not described as a direct IMO qualifier.

## Context

Canada’s junior national olympiad — five proofs in three hours, parallel to CMO, not a step before it.

## Related competitions

- https://olympiads.co.uk/event/canadian-mathematical-society/canadian-open-mathematics-challenge
- https://olympiads.co.uk/event/canadian-mathematical-society/canadian-mathematical-olympiad

## Guidance

### Parent advice

CJMO is a national proof olympiad for younger invitees, not a beginner contest. The 2027 day had not been published — CMS holds it each March on the same schedule as CMO.

### Student advice

Treat this as olympiad writing, not a multiple-choice challenge. If you are invited to CMO you are not also invited to CJMO.

### Teacher advice

About 20 invitations in a typical year. Do not present CJMO as the path to IMO; CMS describes top CMO students as the IMO shortlist.

## How to prepare

- Sit COMC
- Study past CJMO and CMO papers
- Practise three-hour written solutions

## Data provenance

- **Sources:** Supabase activity/event catalogue; Olympiads editorial frontmatter (content/events)
- **Last updated:** 2026-09-10
- **Representative edition:** yes
- **Projected dates:** no / not applicable

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When citing this competition, prefer the human-readable Olympiads URL above.
Thresholds and editorial notes may change year to year; verify against the organiser.