The CEMC, at Canada’s University of Waterloo, runs a contest family written by more than 300,000 students from over 85 countries each year, and U.S. schools are eligible. By grade, the ladder runs Gauss (grades 7-8), Pascal (grade 9), Cayley (grade 10), Fermat (grade 11), and Euclid (grade 12). Motivated students in lower grades may write a higher contest.
For 2026-27 in North and South America: Pascal, Cayley, and Fermat are written February 23-24, 2027 (the official dates document lists Wednesday, February 24); Euclid on April 6, 2027; and Gauss within a window from May 10 to 21, scheduled by the school. Ordering deadlines differ — February 2 for Pascal/Cayley/Fermat at schools outside Canada, March 11 for Euclid, and April 22 for Gauss.
The paper structures are worth noting. Gauss is 25 multiple-choice questions in 60 minutes. Pascal, Cayley, and Fermat are also 25 questions in 60 minutes out of 150, but Part C requires a whole number from 0 to 99, which removes guessing entirely. Euclid is the outlier — 10 questions in 2.5 hours out of 100, with a substantial portion requiring full written solutions marked step by step. All five papers are offered in English and French.
Registration is where U.S. families stumble: students cannot register themselves. A teacher must order through the CEMC Contest Supervisor Portal using the school’s CEMC School Number and supervise the writing. Fees are in Canadian dollars.








