While Brazilian schools lock student phones away, nearly half of the country's 15-year-olds already study with an AI chatbot every week. The Pisa 2025 exam, released on Tuesday by the OECD, shows that 48% of Brazilian students use tools such as ChatGPT at least once a week to learn, against 46% on average across the OECD, the group of mostly wealthy countries that runs the test. It is the first time the exam has measured the habit. The figures were reported by G1, Globo's news portal.
Some context: Pisa, the Programme for International Student Assessment, works like an educational check-up given every three years to 15-year-olds in dozens of countries, testing math, reading and science (science was the focus area in 2025) and surveying students and principals about school life. On AI, the widest gap between Brazil and the OECD average shows up in quick research on a new topic: 40% of Brazilian students turn to a chatbot for that, against 31% on average, the largest contrast of any use the survey measured. Summarizing a school text with AI is a habit for 31% of Brazilians, nearly tied with the 30% average. When it comes to writing a whole essay, Brazil uses less AI than the group: 27%, against 29%. And 11% of Brazilian students say they never turn to technology for schoolwork, a smaller share than the 14% average.
The heavy use comes in a country that has tightened rules against phones at school. According to Folha de S.Paulo, the share of students in schools that ban the device more than doubled in three years, from 37% in 2022 to 81% in 2025, after a national policy that took effect in January 2025; across the OECD, the jump was from 34% to 49%. The OECD ranks the ban among the most effective measures against digital distraction: in schools with one, students are about 13% less likely to report distraction during lessons, on average across the organization's countries. The ban, however, covers the classroom, while homework happens at home, where the chatbot lives. Brazilian schools also lag on infrastructure: Pisa's School Digital Capacity Index places the country below the international average on items such as having an effective online teaching platform and teachers able to blend digital devices into instruction.
For Ernesto Martins, a researcher at the education think tank Iede, the impact of these tools on learning cannot yet be measured. One point he flags is the hurried reading pattern identified by Pisa 2025: students who answer quickly and superficially, and as a result miss questions that would need more attention.
"The world we live in today, of artificial intelligence and faster reading (with social media and other factors), may be hurting less proficient readers and having a global impact on learning, not only in reading but in other subjects as well. The OECD report itself discusses this, and I think we need to reflect on this scenario," Martins said.
What we still don't know
The figures are self-reported by teenagers, with all the margin of error that implies, and because this is the first measurement there is no historical series to compare. Nothing in the survey proves that AI helps or harms learning. It also pays to follow the money: chatbots such as ChatGPT, made by OpenAI, are free because the business of these companies is turning habit into paid subscriptions. A student who learns to study with AI at 15 is a potential customer at 25, and the companies know it.
What to do with this
For families and teachers, the useful question is what students use the chatbot for: researching a new topic is one profile; handing in an essay entirely written by AI is another, and Pisa's own numbers show the latter is less common in Brazil than in the average rich country. Two fronts are worth watching in the coming years: whether the phone-ban debate extends to AI in the classroom, and how school systems respond to the diagnosis of low digital capacity. The next Pisa round, in 2028, may start to show whether a habit that already reaches almost half of teenagers leaves a mark on scores.