At first glance, you’d think the kids were busy doing homework assigned by their teachers in an education app. But as it turns out, that may not be the only reason they’re glued to their phones.

The app Yiqi Xiaoxue Xuesheng, which means “together primary school students” (yeah, the grammar doesn’t sound quite right in Chinese either), is supposed to allow teachers to send through homework for students to complete within the app. Parents can also see their children’s grades and communicate with teachers.

But as state broadcaster CCTV reported, the app also has a function that many parents weren’t aware of: Games.

Students can play different games in the app and earn virtual currency, which is used to buy in-game items and raise digital pets. Users can also spend real money: One father told CCTV that his child spent more than 1,300 yuan (US$187) on games in the app.

According to the report, some students were told to use the app by their teachers, who would receive 30 yuan (US$4.32) worth of credits for use with cell phone carriers, if they download the app and ask their students to do the same. The app’s marketing staff even visited schools to promote the app, the program says.

Yiqi Xiaoxue Xuesheng has apologized and shut down the game section. (Pictures: 法制晚报)

Education apps are starting to gain popularity in China. As of April, there were more than 145 million people using K12 education apps monthly -- a 41% increase from the previous year, according to a QuestMobile report (K12 refers to children from kindergarten up to 12th grade). And it’s not the first time an app has tried to get students to spend more time on it by offering content that's not homework.

Last month, it was found that an app named “Interactive Homework” offered more than 80 games, and regularly published age-inappropriate articles on its official WeChat account, according to Southern Metropolis Daily. Examples included, “What is the most exciting thing you’ve done in a classroom with someone of the opposite sex?” The report said that the WeChat account had more than one million followers as of June last year, most of them elementary and high school students.

There are plenty to read on a “Class break” section on “Interactive Homework”. (Picture: Interactive Homework)

Authorities are taking notice. State media People’s Daily is calling for more regulations, and China’s anti-porn office says it’s launching an investigation.

The games and questionable articles can no longer be found on “Interactive Homework”, but in a section called “recess”, there are still plenty of articles about astrology and random topics trending on the internet.