Juan Marulanda De Los Rios didn’t need to take a three-hour exam—he just wanted to. In a system where language could trip him up, numbers felt like solid ground. 

After returning to Canada after a few years in Colombia, Marulanda De Los Rios soon fell behind in ninth grade classes that required him to read and write in English. But math required no code-switching, and he excelled at it—so unlike his peers, he dove into the University of Waterloo’s Canadian Computing Competition (CCC) and other exams throughout high school just for the challenge. 

Students around the world enroll in the gruelling CCC to better their chances of being accepted into Waterloo’s prestigious computing and engineering programs, or land a spot on teams to represent Canada in international competitions, he said. The university’s competitive STEM programs have produced a number of esteemed alumni, including RBC’s chief executive Dave McKay, BlackBerry founder Mike Lazaridis and Social Capital CEO Chamath Palihapitiya.

The CCC’s website says while the contest is not required for acceptances into Waterloo’s faculty of mathematics, “strong performance” can help students with admissions.

But this year, the competition didn’t release scores as they typically do. Instead, co-chairs J.P. Pretti and Troy Vasiga released a statement explaining that official results would not be published for the 2025 competition.  

In it, they explained that a large number of students violated its rules. “It is clear that many students submitted code that they did not write themselves, relying instead on forbidden external help,” the co-chairs wrote. Students are usually publicly ranked in the results based on their score, and it would be unfair to do so this year, it said. 

The competition prohibits the “use of AI and other external tools,” a policy that contest participants had to review, University of Waterloo spokesperson David George-Cosh said in a statement to The Logic. He declined to comment on the record about how many students violated the rules, or specify what tools students used to cheat.  

But using AI to cheat has become increasingly prevalent. Academic integrity software TurnItIn found that 11 per cent of 200 million papers submitted between April 2023 and April 2024 had at least a fifth written by AI. Around three per cent were almost completely written by AI.

Jayden, a student who took the test this year, said he wasn’t too surprised that the scores were cancelled. “There’s a lot of cheating around with the rise of AI,” he said. The test is usually taken in schools with teachers supervising screens as the primary way of preventing it, he and Marulanda De Los Rios said.

Jayden recalls one teacher had to keep an eye on eight students during his exam. There weren’t strict barriers to bringing code into the competition or a way of restricting access to websites and applications, he said. 

When Marulanda De Los Rios took the exam in 2022 and 2023, it was more difficult to cheat, but now with Copilot—GitHub’s easily embeddable AI coding assistant—students don’t even need to leave their program to cheat with AI. “Teachers have to be more aware,” he said.

Other major global coding competitions are struggling to keep up with AI-savvy high schoolers cheating on tests. Jayden said he also participated in portions of the USACO, a major U.S. computing competition, where he noted skirting the rules might have been even easier. He said the competition didn’t lock screens, allowed access to websites and could even be taken from home. The USACO’s website clarifies that the use of generative AI is prohibited in the test.

University of Waterloo’s Centre for Education in Mathematics and Computing, which hosts the CCC, plans to take “additional measures to safeguard future competitions.” This includes improved technology, supervision and “clearer communication” for students and teachers, George-Cosh said in a statement.

The decision to cancel the release of this year’s results will weigh most on Grade 12 students who won’t get a chance to do it again next year, Jayden said. But he didn’t think the onus was on the university. “It’s obviously a cheater’s fault, right? They’re the ones who cheated. They’re the one to break the rules. It’s their fault morally and logically.”

The test is “very important” in Waterloo admissions, and can also boost chances at other universities, Jayden said. The exam is often considered when applying to internships, jobs or work experience programs, he said.