How to make learning as addictive as social media | Luis von Ahn

0:00Hey y 'all, Elise Hugh here. My three daughters just headed back to school with new backpacks, new teachers, and all that first day energy. And back to school season can make me feel like a student again, too. So for this month's TED Talks Daily playlist, we have gathered five of our favorite talks about learning, teaching, and the joy of staying curious. No textbooks required. Happy listening.

0:26You're listening to TED Talks Daily, where we bring you new ideas to spark your curiosity every day. I'm your host, Elise Hu. I have been using Duolingo to learn Korean, and I definitely could say at times I've been really hooked. Like many of us feel, I don't want to lose my streaks. So how did the app make language learning fun? In this archive talk, educational equity technologist Luis Van Ahn shares how Duolingo's developers harness the psychological techniques employed in social media and gaming apps to make the app compete with addictive platforms. And in doing so, how they've been able to spread access to language education across the world.

1:06Stick around after his talk for a brief Q &A between Luis and TED's head of media and curation, Helen Walters. We'll dive into this talk right after the break.

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3:13And now, our TED Talk of the day. So, I'm from Guatemala. So, Guatemala is right below Mexico. And for the Americans in the audience, and let this sink in because it really applies in most ways, for the Americans in the audience, you can think of it as Mexico's Mexico. Just like the U.S. doesn't want illegal immigration from Mexico, Mexico doesn't want illegal immigration from Guatemala. It's a smaller country. It's a poorer country. And, well, what can I tell you? It has much better Mexican food.

3:51Guatemala is a very poor country. And a lot of people talk about education as something that brings equality to different social classes. But I always saw it as the opposite, as something that brings inequality. Because what happens in practice is that people who have a lot of money can buy themselves a really good education and therefore continue having a lot of money, whereas people who don't have very much money barely learn how to read and write and therefore never make a lot of money, and this is especially true in poor countries. Now, I was fortunate that I received a rich person's education, even though I didn't grow up rich, and it's because I'm an only child, and my mother, who was a single mother, spent all of her resources on my education.

4:30And this allowed me to come to college to the U.S. and eventually get a PhD in computer science. Now, because of all of this, about 10 years ago, I decided I wanted to do something that would give equal access to education to everyone. Oh, by the way, this is what I want to talk to you about today, giving equal access to education to everyone. At the time, I was a professor of computer science at Carnegie Mellon University, and I decided to work on this with my PhD student, Severin. The way my brain works, all of education is just too general of a problem. So I decided, let's start by teaching one thing.

5:08And then I started thinking, OK, well, what should we teach first? Should we teach math? I mean, we both loved math. Me and my co-founder, we both loved math. And, you know, we didn't decide to do math. Then we started thinking, well, maybe we should teach computer science. But eventually, and this may be surprising to people in North America, eventually we decided that the best subject to start with was teaching foreign languages. And let me tell you why. There's a number of reasons. One of them is that there's a huge audience for it. There's about two billion people in the world learning a foreign language, both in school and outside of schools.

5:42Most of these people, by the way, are learning English. About 80 percent of them are learning English. And the reason for that is because English can truly transform your life. In most countries in the world, knowledge of English can significantly increase your income potential. So this is another reason why we decided to start with foreign languages, and it's because you can directly make more money if you learn another language, in particular English. And see, this is pretty different than many other subjects. For example, take math. In the case of math, just knowledge of math does not increase your income potential, because usually you have to learn math to then learn physics, to then become a civil engineer, like that's how you make more money.

6:16Whereas with languages, if you were a waiter and you learned English, now you can be a waiter at a hotel and make more money. So we decided, well, let's get started by teaching languages. Now, we also convinced ourselves that the only way to really reach a lot of people was by using a mobile phone, or a smartphone in particular. See, building schools all over the world is simply too expensive. On the other hand, most of the world's population already has access to a smartphone, and the trend is that that fraction is only going to increase. So we decided at the time that we would make a way to learn foreign languages on a mobile phone that was accessible to everyone.

6:54And then we called it Duolingo. In order to truly be accessible to everyone, rich and poor, Duolingo uses a freemium model to support itself. What that means is that you can learn as much as you want without ever having to pay. But if you don't pay, you may have to see an ad at the end of a lesson. Now, if you don't like ads, you can also pay to subscribe to turn off the ads. And it turns out that the vast majority of the revenue for Duolingo comes from people to pay to subscribe to turn off the ads. Now, who are these people who pay to subscribe to turn off the ads? Well, they're usually people, well-off people, in rich countries like the U.S.

7:31and Canada. Who are the people who don't pay to subscribe? They usually come from poorer countries like Brazil or Vietnam or Guatemala. So what I like about this model is that it is a small form of wealth redistribution because we're basically getting the rich people to pay for the education of everyone. So with smartphones, we can reach a lot of people and we can even get the rich people to pay for the whole thing. This is great. However, if you're trying to deliver education with a smartphone, you run into a humongous problem. And it is that smartphones come equipped with some of the most addictive drugs that humanity has ever engineered.

8:03TikTok, Instagram, mobile games. See, delivering education over a smartphone is like hoping that people will eat their broccoli, but right next to it, you put the most delicious dessert ever made.

8:16If you really want to deliver education to everyone, not only do you have to make it accessible, but also you have to make it so that people want to actually learn. And with Duolingo, we've been able to do this, and at the highest level, the way we've done this is by making the broccoli taste like dessert. I'll say it another way. What we've done is that we've used the same psychological techniques that apps like Instagram, TikTok or mobile games use to keep people engaged, but in this case, we use them to keep people engaged with education. Let me give you some examples of these techniques. One of the most powerful ones is the notion of a streak.

8:53What a streak is, it's just a counter that measures the number of days that you've used the product consecutively. You just take that number, you put it very prominently in your product, and then people come back every day. And the reason people come back every day is because, well, if they don't come back, that number resets to zero, and people don't want to lose their streak. It works. Now, on the one side, streaks have been criticized for, for example, getting teens addicted to Snapchat. But in the case of an educational app, streaks get people to come back to study every day. Now, to give you an idea of the power of streaks, in the case of Duolingo, we have over three million daily active users that have a streak longer than 365.

9:41That means they haven't missed a day in the last year or longer. Now, fun fact about streaks. What country do you think has the longest average streaks for an educational app? It's Japan. Of course. Shortest average streaks? Latin America, baby. But we're fun. Hey, we're fun.

10:06Another important mechanism to get people to come back to your product are notifications. On the one side, notifications can be really spammy and annoying, But in the case of an educational product, people actually want to be reminded to learn. In the case of Duolingo, we have a very sophisticated AI system that basically chooses when to send a notification and also what to say in each notification to maximize the probability that people come back. Now, interestingly, even after all this sophistication, it turns out that the algorithm for choosing what time to send you a notification is pretty simple.

10:39You know what is the best time to send people a notification? I'll tell you. It's 24 hours after they use the product last. Because, and there's an easy explanation, if you were free yesterday at 3 p.m., you're probably free today at 3 p.m. as well. So this is what very sophisticated millions of dollars of AI found. It's funny. Now, with notifications, you shouldn't be spamming. And we're not spamming. With Duolingo, we actually stop sending notifications after seven days of inactivity. So if you don't use Duolingo for seven days, we stop sending you notifications. Now, at some point, it occurred to us, If we're stopping to send people notifications, we should let them know.

11:16So we started sending this notification to people, saying, hey, these reminders don't seem to be working. We'll stop sending them for now. You know what people do when they get this notification? They come back.

11:29Passive-aggressive. Works for my mother, works for Duolingo. I go...

11:41These passive-aggressive notifications are really good at getting people to come back because they feel like our green owl mascot has given up on them. So they come back. And speaking of our green owl mascot, by the way, because all our notifications come from our green owl mascot, and, well, he's passive-aggressive and also pretty pushy, this has given rise to a lot of memes on the internet that make fun of just the great lengths that he will go through to get you back to learn a language. Now, Duolingo has entered the zeitgeist, and there's thousands of memes, there's SNL skits about it, and it's because we've managed to get people to want to learn a language by using the same techniques that mobile games and social media use to get people engaged.

12:23And this is a really important point, let me say this. I don't actually believe that there's a way to make an educational app be as engaging as something like TikTok or Instagram or mobile games. But the good news is that, and by the way, the reason I don't believe that is because ultimately you have to teach people something, and it's hard to compete with cats and celebrities. But the good news is that I don't think you have to. See, here's the thing. When you're learning something, you get meaning out of it. Whereas when you're scrolling for two hours on Instagram, a lot of times afterwards, you feel like you just wasted your time.

12:57So I think it's actually okay if your educational product is only 80 or 90 percent as engaging as something like TikTok, because the other 10 or 20 percent will be provided by people's internal motivation. Though, of course, not much more than that. This is really a key point. If you want to get people to do something meaningful, you can use the same techniques that apps like social media use to get people to do it. And even if you're not as engaging as those apps are, you can still get hundreds of millions of people to use your product. In the case of Duolingo, for example, there are more people learning languages on Duolingo in the United States than there are people learning languages across all U.S.

13:35high schools combined. And this is true in most countries in the world. My hope is that, I know we can do this, but my hope is that as humanity, we can do what Duolingo has done for learning languages, but for all other subjects, where we can get people to learn math with mobile phones, like millions of people to learn math with mobile phones, or physics, or whatever. I hope for a future in which screen time is not a bad thing, in which we can deliver high-quality education to everyone, rich or poor, using a mobile phone. But the single most important thing that I can end this talk with is a reminder to please, pretty please, I beg you, do your language lessons today.

14:18Thank you very much. Thank you. Thank you.

14:30Luis, thank you so much. Thank you. I wonder if you can just say a little bit more about that last point, about how do you think that you can apply this type of thinking to other subjects? So you mentioned math, you mentioned things like that. How do you do that? Yeah, I think in particular subjects that are learned through repetition. And it turns out most things that are really meaningful are learned through thousands and thousands of repetitions. You learn to read through repetition. You learn elementary school math through repetition. Most things that you can learn through repetition, you can actually gamify and turn into something like Duolingo, where people just do it a lot and do it fun.

15:05It's a little harder for things like explanations. That probably is going to require some really good videos. Sal Khan is doing a really good job with that. But for things that require a lot of repetition, I think we can use the same methods. Amazing. Thank you so much for sharing your life. Thank you.

15:22That was Luis von Ahn at TED 2023. This talk was originally posted in October 2023. If you're curious about TED's curation, visit ted.com slash curation guidelines. And that's it for today. TED Talks Daily is a podcast from TED. This episode was produced and edited by our team, Martha Estefanos, Oliver Friedman, Lucy Little, Emma Taubner, and Tansika Sungmar Nivong. Additional support from Daniela Ballarezzo, Christopher Faze-Bogan, Valentina Bohanini, Banban Chang, Brian Green, and Lainey Lott. Learn more at podcasts.ted.com. I am Elise Hu. Thanks for listening.

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17:26Yep. Even on weekends, it's pretty much all he talks about in a good way. What's in your wallet? Terms apply. See CapitalOne.com slash bank. Capital One N.A. Member FDIC. Hey, we're Nick and Jack hosts of The Best One Yet. Behind every episode, there's research, email, spreadsheets, and our shared Google Doc, the headline hammer. With Google Workspace with Gemini, Google's AI is built right into the premium versions of tools we already use, like Gmail, Docs, and Sheets. No new tools or extra logins, just personalized AI for the way we work. That means less time on the work around the work and more time finding the stories worth talking about.

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