A few days ago, I shared the World Bank’s summary of the results of the PISA for Schools assessment conducted in 171…

A few days ago, I shared the World Bank’s summary of the results of the PISA for Schools assessment conducted in 171 Salvadoran public schools participating in our education pilot. Since then, I have seen some legitimate questions about what these results mean, as well as some claims about what they supposedly don’t mean. So let’s be very precise. First, what we NEVER claimed: 1. We never claimed these results represent the national average. They don’t. This was not the national PISA assessment. It was PISA for Schools, conducted specifically in the 171 public schools participating in our pilot program. That is precisely why my original post said: “These are the results of our pilot program, which includes AI tutors and has been running in 171 public schools for just over a year.” A pilot is, by definition, not the entire country. 2. We never claimed that these 171 schools were a statistically representative sample of every school in El Salvador. They weren’t selected randomly from all Salvadoran schools. They were selected to participate in the pilot because they were schools where the program could initially be implemented more easily: they had certain basic infrastructure and connectivity requirements, and school communities capable and willing to implement a new educational model. That creates a selection effect, and it should be acknowledged. But there is an important distinction here. These schools were NOT selected because their students had exceptional academic results. They were not our “best schools.” Not even close. We didn’t search the country for the highest-performing schools or students and then test them. They are normal Salvadoran public schools, urban and rural, in different parts of the country, serving ordinary Salvadoran families. And the characteristics that made implementation easier: connectivity, infrastructure, trained teachers and willingness to adopt the program, are also things that can be replicated in other schools. They are not innate characteristics of the students. We can install connectivity. We can improve infrastructure. We can train teachers. We can provide the same technology. We can deploy the same educational tools. In fact, that is exactly what we are doing. 3. These results also do NOT prove that AI tutors, by themselves, caused the improvement, although we believe they are a MAJOR part of these results. Our pilot is broader than that. It includes changes in teaching, support for teachers and principals, educational materials, monitoring and evaluation, technology, and AI tools, among other interventions. Our AI tutors and learning platforms are being developed with @grok, @Kira_Learning, and support from I Hate Flying Bugs. And the broader transformation of our education system is being supported by the @WorldBankGroup, @AgendaCAF, and @el_BID. All of these interventions can also affect student motivation and engagement. But that distinction matters: if students become more motivated BECAUSE of the program, that is not necessarily a flaw in the program or an explanation that somehow invalidates the results. It may be one of the ways the program works. The same applies to teachers. For example, the implementation of the AI tutors, including the requirement for teachers to log in and out of the system, coincided with teacher attendance in these schools increasing from 76% to 97%. If the program causes teachers to attend school more consistently, and that in turn helps students learn more, that is not an advantage that disappears when we scale the program. It is potentially part of the intervention itself. Of course, to scientifically isolate the causal effect of AI tutors, teacher attendance, student motivation, technology, training, or any other individual component would require a different experimental design. Now, what DO these results tell us? 1. They tell us that 1,198 students in 171 ordinary Salvadoran public schools… 🧵1/2👇🏼

vittorio@IterIntellectus · Sep 6, 2026

honestly, i keep thinking about this result and it's just absurd. in the 2022 PISA, el salvador scored 343 in math, 365 in reading, and 373 in science near the bottom of PISA, close to guatemala and dominican republic now the country has developed a program for education modernization in a pilot group of public schools with 1:1 AI tutoring and personalized learning after the pilot had been running for BARELY OVER A YEAR, students got results comparable to germany and sweden. that's more than an entire standard deviation that is fucking insane we should be talking about absolutely nothing else if you actually care about poor children and equality of opportunity, the possibility of giving every child on earth an individualized tutor for a fraction of the cost of human 1:1 tutoring should be one of the most exciting developments in human history. "it's all in the environment tards" should be drooling at the news every government on earth should be running massive randomized trials of this right now, and if the effect survives, scaling it as fast as physically and humanly possible for every child on earth the funniest part is that while the supposed "fascists" are celebrating poor kids learning, the people supposedly obsessed with inequality are barely talking about it, and if anything are banning AI in schools revealed priorities are funny like that

Now, what DO these results tell us? 1. They tell us that 1,198 students in 171 ordinary Salvadoran public schools participating in this program were independently assessed using an internationally comparable instrument. And their results in reading, mathematics and science were comparable with the average results of students in Germany and Sweden. That is a fact, supported by an internationally recognized OECD assessment and reported by the World Bank. 2. They tell us that achieving those levels of performance in Salvadoran public schools is POSSIBLE. This is perhaps the most important finding. For decades, we have been told that transforming education takes generations. That poverty determines educational outcomes. That our public schools simply cannot compete with schools in developed countries. Yet here we have Salvadoran children, attending Salvadoran public schools, taught by Salvadoran teachers and supported by AI tutors, inside our existing public education system, obtaining results comparable with students in some of the world’s most developed countries. Does that prove that every Salvadoran student is already performing at that level? Of course not. But it proves something enormously important: There is nothing inherent about being Salvadoran, attending a public school, coming from a lower-income family, or living in a developing country that prevents a child from reaching those levels. 3. It tells us that the conditions associated with these results appear to be replicable. Imagine that the explanation were that we selected 171 elite private schools, filled them with the country’s wealthiest children, and then announced their scores. That would tell us almost nothing about whether the model could work nationally. But that’s not what happened. These are ordinary public schools. The advantages associated with participation in the pilot: better tools, connectivity, infrastructure, teacher support, technology and a different educational model, are precisely the things the Government can reproduce. That doesn’t guarantee the same results when we scale. But it gives us a very good reason to try. 4. It tells us that expanding the program is worth doing. A pilot is not supposed to prove that something already works everywhere. If it did, it wouldn’t be a pilot. A pilot asks a much simpler question: “Does this approach show enough promise under real-world conditions that we should expand it and test whether the results can be reproduced at a much larger scale?” The answer from these results is clearly yes. The World Bank itself described the results as promising and encouraging evidence ahead of the expansion of the reform. 5. The real test begins NOW. Going from 171 schools to more than 1,000 schools is much harder. Going from 1,000 schools to every public school in El Salvador will be harder still. Scaling introduces new problems. Some schools have weaker infrastructure. Some have worse connectivity. Some teachers will adapt faster than others. Some communities face greater social and economic challenges. And implementation quality can decline as a program becomes larger. All of that is true. And that is exactly why we are scaling progressively. The next question is not whether 171 schools can do it. We now know they can. The question is whether 1,000 can. Then whether several thousand can. And ultimately whether an entire national public education system can. That is what we intend to find out. 6. And yes, the future national PISA results that will be published in 2029 will matter enormously. Those will tell us something different. PISA for Schools tells us what is happening in the schools participating in this reform. National PISA will tell us what is happening across the country. Those are different questions, and serious people should not confuse them. 2/2🧵👇🏼

As the reform reaches more and more schools, national assessments will allow everyone, including our critics, to judge whether the gains observed in the pilot are spreading throughout the system. If they aren’t, we will have to understand why and fix it. If they are, then we keep going. That’s how evidence based public policy should work. So no, these results do not prove that El Salvador already has the educational outcomes of Germany or Sweden. They don’t prove that every Salvadoran school has been transformed. And they don’t prove that every element of our reform works equally well. What they DO show is that ordinary Salvadoran children in ordinary Salvadoran public schools, when given a radically improved educational environment, can achieve results that most people would have considered impossible for our country only a year ago. These 171 schools were the proof of concept. Now comes the difficult part: reproducing those results across an entire country. More than 1,000 schools are already implementing the program. Within 18 months, every public school in El Salvador will be. Then, we’ll have a lot more data. We are not afraid of that. We are betting on it 🇸🇻