Mexico’s National Autonomous University (UNAM) has ordered a new in-person entrance exam for nearly 58,000 applicants after its first fully online admissions test produced a sharp surge in top scores and set off cheating allegations.
UNAM said that in its 120-question entrance exam, the share of applicants scoring above 100 points had stayed at 3.5% over the past five years, from 2021 to 2025. This year, that figure rose to 16.3%. The share scoring above 110 points also jumped, from 0.9% to 5.5%. A total of 158,723 people sat for the exam.
First fully online exam draws scrutiny
From late May to early June, UNAM moved the admissions exam fully online for the first time. The setup combined a locked browser, AI-based camera proctoring software and manual review.
The locked browser was designed to keep a candidate’s computer on a single exam screen, preventing tab switching or the opening of other programs during the test. The AI proctoring system used the camera to track the test taker’s face and nearby movement in an effort to detect suspicious behavior.
Even with those controls, about 2% of exam papers were ultimately voided. The university’s technical committee found three main forms of misconduct: using a mobile phone during the exam, receiving help from another person nearby, and having someone else impersonate the registered candidate.
The report said proctoring software could see the face in front of the camera, but could not detect what was placed in a candidate’s ears or what happened outside the visible screen area, such as notes being passed by hand.
UNAM adopts full retest plan
After results were released, accusations of cheating mounted quickly. UNAM then formed a technical committee to investigate. On July 31, committee member Eduardo Bárzana García presented the panel’s conclusion: rather than trying to sort out who cheated and who did not one by one, the university should discard the results and hold a controlled in-person exam.
UNAM adopted a four-part plan: hold a new controlled test, call back all applicants this year who had reached the admission threshold, use multiple versions of the paper exam to reduce answer sharing, and base final admission outcomes entirely on the new test scores.
The scope is broader than only those already admitted through this year’s online exam. It also includes all applicants whose scores reached the minimum admission cutoff recorded by each program between 2021 and 2025. Combined, those groups amount to an estimated 58,000 people, all from this year’s pool of 158,723 applicants. No existing students are affected.
Timeline pressure before the academic term
That means many applicants who met the standard without cheating will still have to prepare again and retake the exam. UNAM had originally scheduled the start of the academic term for Aug. 10. Details of the controlled exam now need to be finalized quickly, or the opening of the term could also be delayed.
UNAM rector Leonardo Lomelí said in an official university publication that honest applicants had done nothing wrong but would still need to prepare again and sit for another test. He said the controlled exam was necessary to provide certainty and protect fairness in admissions.
The fallout also spilled onto campus. On July 24, the university temporarily suspended registration. Three days later, students took to the streets to demand an explanation from the administration.