Duolingo, best known for its whimsical owl and language-learning app, is working on a new product to add to its growing suite: a math app, according to CEO Luis von Ahn. The co-founder mentioned the app during an interview last week, the same day that Duolingo officially listed in the stock market.

After the interview, TechCrunch reached out to Duolingo to get more information about the app, but the company declined to provide more detail because it is “still very early” in the development process. It did say that users may learn more about it later this month at Duocon, Duolingo’s annual free conference. A May job posting shows that Duolingo has been looking for a learning scientist with a PhD in mathematics to help build out a new math app alongside a “small cross-functional team.”

The listing hints that the app will be focused on serving younger learners. It mentions that Duolingo wants candidates to have classroom experience and knowledge about teaching K-12 level math, especially with younger students between 3rd and 8th grade.

Duolingo’s current users feel mixed about the idea of Duolingo getting into math.

In an interview on IPO day, CEO Luis von Ahn said that users may see Duolingo accelerate its math app and that the company plans to expand beyond language learning through upcoming acquisitions. That may calm some qualms around Duolingo needing to put a ton of resources toward an entirely new piece of software or curriculum.

“If there are other subjects where we think somebody is doing a pretty good job and they have a similar mission to us, and they have a similar company culture,” Duolingo may consider acquiring the company, von Ahn said in the interview.

Math-focused edtech companies include Khan Academy, Brilliant.org, Photomath, Numerade and the recently acquired Symbolab.

For Duolingo, the math app is another chapter in its history of experimentation. The company has churned through hundreds of ideas in its decade of existence, which have had varying degrees of success.

Over the past few years, it built a product suite beyond its core app, which includes Duolingo ABC, a literacy app for kids and the Duolingo English Test. Meanwhile, Duolingo’s “graveyard” of failed ideas includes a few retired monetization strategies and AI-powered chatbots. Popular features like leaderboards sputtered before they succeeded. And math, interestingly, has always been in the back of von Ahn’s head.

As mentioned in the Duolingo EC-1, von Ahn has always said that he and his co-founder, Severin Hacker, were thinking about making Duolingo a math app before they eventually decided on language learning.

“I love math, but if you learn math, math itself can’t make you any money,” von Ahn said in a previous interview. “You learn math to learn physics to become an engineer, whereas knowledge of English directly improves your income potential in most countries of the world.”

One user wrote that “[math] is such a key skill to learn…[and] hopefully this may provide better resources especially to those with such limited access, while being inspirational and equally engaging to those of us with more opportunities.”

Others seemed to want Duolingo to invest inwardly on its language-learning service before moving outward to other areas. “It’s odd that Duo should consider branching into Maths when its coverage of the majority of languages (with the notable exception of French and Spanish) leaves a great deal to be desired,” one user wrote.

The company can only teach from a beginner to a low-intermediate level of language fluency according to the Common European Framework of Reference for Languages (CEFR). About 30% to 40% of Duolingo courses are in some stage of CEFR alignment, per the company’s last pull of metrics from May.

It may be too soon to assume how Duolingo’s math app would look, what it would offer or even if it will be monetized. Regardless, it will be Duolingo’s first formal foray into an area of education beyond language.

The company will need to find not only the product, but the philosophical overlap between the two subjects. Language learning is a skill that is benefited by cultural context and nuance, while math revolves around the goal of getting to the one right answer. However, both areas of education require methodical thinking and the ability to apply functions to get to answers. Ultimately, both rely on what Duolingo often argues is its biggest product: motivation to open up an app, and pay attention to what’s happening on the screen.