How to make learning as Addictive as social media

I’m from Guatemala, and just to clear things up—that’s not where they keep the prisoners. That’s Guantánamo. Not the same place. Guatemala is just below Mexico, and for the Americans in the audience, think of it this way: just like the U.S. doesn’t want illegal immigration from Mexico, Mexico doesn’t want illegal immigration from Guatemala. It’s a smaller, poorer country—but with much better Mexican food.

Growing up, I always heard people say that education brings equality, but I saw the opposite. Wealthy people can afford a great education, which helps them stay rich, while poor people often only learn the basics and remain stuck in poverty. This is even more extreme in poor countries like mine. I was lucky, though. Even though I wasn’t rich, my mother—who was a single mom—put all her resources into my education. That gave me the opportunity to study in the U.S. and eventually earn a PhD in computer science.

About ten years ago, I decided I wanted to do something to give equal access to education to everyone. At the time, I was a professor at Carnegie Mellon University, and I teamed up with my PhD student, Severin, to work on this. Education as a whole is a massive problem, so we decided to start small by teaching just one subject. We considered math, since we both love it, and even thought about computer science, but in the end, we landed on foreign languages.

Why languages? First, there’s a huge demand—about two billion people worldwide are learning a foreign language, mostly English. In many countries, knowing English can significantly increase your income, which isn’t the case with most subjects. For example, just knowing math won’t necessarily raise your salary, but if you’re a waiter and you learn English, you can get a job at a hotel and earn more right away.

We also realized that the best way to reach millions of people wasn’t by building schools—it was through smartphones. Most of the world already has access to them, and that number is only growing. So we created a mobile language-learning platform that would be completely free and accessible to everyone. We called it Duolingo.

To keep it free, we use a "freemium" model: you can learn as much as you want for free, but if you don’t want to see ads, you can pay to remove them. Interestingly, most of the people who pay for ad-free access are from wealthier countries like the U.S. and Canada, while users from poorer countries, like Guatemala or Brazil, tend to use the free version. In a way, this means rich people are paying for the education of everyone else, which I think is pretty cool.

But delivering education through a smartphone comes with a big challenge: smartphones are filled with incredibly addictive apps like TikTok and Instagram. Getting people to focus on learning is like expecting them to eat their vegetables while putting a delicious dessert right next to them. So, we decided to make the “vegetables” taste like dessert. In other words, we used the same engagement techniques that social media and mobile games use—except we applied them to learning.

One of the most powerful techniques we use is the concept of a "streak"—a counter that tracks how many days in a row you've used the app. People don’t want to lose their streak, so they come back daily. We also use smart notifications to remind people to practice at just the right time, usually 24 hours after they last used the app, since that’s when they’re most likely to be free again.

At some point, we noticed that after seven days of inactivity, we stopped sending notifications. So we decided to let people know. We started sending messages saying, "These reminders don’t seem to be working, so we’ll stop for now." Guess what happened? People came back! Turns out, a little passive-aggressive push works—just like my mom’s guilt trips.

All our notifications come from our green owl mascot, who has developed a bit of a reputation for being pushy. People started making memes about how Duolingo will go to extreme lengths to remind you to practice. My favorite one? It shows a home security alert saying "Intruder detected," and the caption reads, "Looks like you forgot your Spanish lesson."

Duolingo has become the world’s largest language-learning platform. In the U.S., more people learn languages on Duolingo than in all high schools combined. And this is true in most countries. I believe we can apply the same approach to other subjects, especially ones that require repetition, like math or reading. If we can do for those subjects what we did for language learning, we could completely change how people access education.

I hope for a future where screen time isn’t seen as a bad thing, but as a tool for high-quality education that’s available to everyone. But before I go, I have just one last request—please, pretty please, do your language lesson today.

Thank you!