With HQ Trivia continuing its viral and popular run, and education remaining a perennially strong category in app stores, it was only a matter of time before someone came along that combined elements of both to hitmaking effect. Kahoot, an app based out of Oslo, Norway that aims to teach its users across a wide variety of subjects and ideas by way of quizzes that they take in competition with others either on their own or in live classroom environments, could be the one.

The startup today is announcing some hefty milestones. With 51 million Kahoot games now built on its platform (yes, 51 million) by its users and by Kahoot itself, the startup says that its app and site are now being used by 70 million monthly unique users, a combination of businesses that use Kahoot’s app for training purposes, and students and teachers who use it for more traditional learning.

That number, up 75 percent in the last year, includes 50 percent of all the students in the US, kindergarten through twelfth grade (or 30 million out of an estimated 60 million), up from 30 percent in April of last year; and 47 percent of all teachers in the US. It also includes 1 million employees from the business world. The company has seen 1.6 billion players cumulatively since launching in 2011, including 1 billion in the US alone.

It’s a huge leap for a startup originally started as an idea from Alf Inge Wang, a professor from the Norwegian Computer Science and Game Technology professor at the Norwegian University of Technology and Science (NTNU) in Trondheim, Norway.

Originally called Lecture Quiz in 2006, the tech comes from Wang’s student Morten Versvik for his Master’s degree at NTNU. Later Jamie Brooker, Johan Brand and Asmund Furuseth joined the company while at a creative agency called We Are Human, where they worked on the UX and design of Kahoot. Eventually they wound down We Are Human and Kahoot raised seed funding after seeing some early traction. (All five are the co-founders of the startup.)

Kahoot’s supercharged growth, particularly in the US, eventually helped it close out a Series A round of $20 million last year, bringing its total raised to $26.5 million. Notably, its investors included strategic stakes from Disney and Microsoft, along with Nordic VC biggies Northzone and Creandum.

Now the company’s surge is driving the startup to its next phase. We understand that Kahoot is gearing up to raise a bigger Series B this year, to help it forge more partnerships aimed at producing a wider range of content particularly through its own Kahoot Studio, to develop its monetization, and to become a cornerstone in how people are using technology as a supplementary way to learn, whether it’s in school or at work.

Partnerships are already figuring in an interesting way at the company. According to Kahoot’s CEO Erik Harrell, Disney is working with Kahoot on ways of incorporating some of its iconic brands into its quizzes, as another way of engaging students to use them.

Microsoft, which already has a strong foothold in the education space, is used as a sign-in option for people who want to Kahoot with others. (Google, not an investor but also doubling down on education these days, is the other profile log-in option, alongside email.)

Kahoot’s growth is an interesting development, as it underscores a trend of how the worlds of educational and gaming apps have been intersecting for years. And when you think about it, that makes a lot of sense: gamification has long been seen as a useful trick for engaging people to learn, and not all games are based on dexterity; many are based on knowledge and information.

It’s not the only one tapping the opportunity in educational apps today. Startups like VIPKID and Age of Learning were last respectively valued at $1.5 billion and $1 billion, and in addition to Microsoft, the likes of Apple and Amazon are also eyeing up the opportunity in the education sector.

It’s noteworthy to me that Amazon also has a strong games business, its Twitch network and a growing interest in developing and commissioning its own original media content: combining all these, you could see how it, too, could build out its own Kahoot-style service.

For the record, there doesn’t appear to by any acquisition talk between Kahoot and Amazon, although I’ve heard they have talked partnerships. All told, I don’t think this is the end of this story.

Here are some excerpts from an interview I had with Harrell on the occasion of their milestone figures, in which he talks about Kahoot’s popularity, its business model, and how to monetize without raising the hackles of regulators trying to protect minors.

There have been a ton of educational apps on the market. Not all of them have grown like Kahoot has. What’s going on?

It really started with the product: people just like the idea of a quiz and the fun and competitiveness that comes with it. It’s like a quiz show. There is also something here about inclusivity. Every student is engaged, and no one is left out, in this format. This is different from a traditional classroom, where some will always be engaged, and some are bored. It seems that at some level, everyone can and wants to compete on Kahoot.

The other thing is teachers. We have had strong teacher engagement and growth in the second half of the year. What we are seeing is that many teachers in the US — we started in the US and have been there longer — are making it a part of their teaching platform. The word of mouth among teachers has been a big part of it.

How are you making money? 

So far we have been focused mostly on user growth K-12. The initial focus for commercializing has been around companies, with 25 percent of Fortune 500 companies now using the product. We only launched the premium business service in October of last year but we already have companies like Facebook, Uber, PwC and really well known brands using it for training, sales and HR, and retail training. On the corporate side it’s a platform play for companies to have the tools to create their own Kahoots, or something we can create in the Kahoot Studio.

For students, we have a big ambition around premium content, which we’ll develope ourselves but also with partners. Over time we want to bring lots of content providers on to the platform. People can consume all kinds of stuff, not just Kahoot-created.

What about the fact that a lot of school systems lack money, and that teachers are already feeling a lot of pressure to fork out from their own wallets to buy materials for classrooms? And also that some parents don’t have the resources to buy apps for their kids? 

We are sensitive to that issue about the lack of funds, so the initial focus we will have is sponsorships. There are corprorate sponsors we are in dialogue with now, many who want to support education, and sponsoring content on Kahoot is a great way to do that.

We also believe in a subscription service. We have already found that there are many who are willing to pay subscribe, school districts that want to enable teachers and also parents.

How do you see content on Kahoot developing over time?

Most of the content is user generated today, but over time we want to be more of a publisher, we are open now and want to be in the future, and we also want to bring third parties into the mix. Our announcement with Disney and ESPN to pilot Kahoots around LucasFilm and ESPN in academic Kahoots is one example. We think this could be a great way to engage some kids, teaching science and math through film. Others might be Kahoots tagged to textbooks, say from established publishers like Pearson and McGraw Hill. Our focus will be on making quizzes though, complementary not replacing these.

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