In 2022, Yuan recorded his classes and uploaded them to Douyin, as some of his students had to leave school to prepare for the entrance examination for art college.

They immediately became an online sensation.

His followers were first amazed by his improvised drawings, which cover phenomena such as the Earth's rotation and revolution, and were also drawn to his fascinating explanations of what lies behind even the most mundane phenomena, knowledge that Yuan made easily accessible.

From a geographic perspective, he showed the reasons for the distinctive fragrance of jasmine flowers in Hengzhou in the Guangxi Zhuang autonomous region, and how Guizhou's provincial capital Guiyang derives its name.

Many viewers left comments saying they never realized the subject could be so enjoyable during their school years, and how the videos have helped them see things they used to take for granted in a fresh light.

Yuan's online followers even started to ask him geography-related questions about personal geographic experiences and difficult topics from high school geography exams, which have all been a source of inspiration for new science videos.

Yuan records videos addressing these questions, often using his signature blackboard drawings to clarify important points for viewers.

The comments on his videos often lead to debates and discussions about geography.

"This shows that people's curiosity for nature is universal, and in each individual there is a geographer," Yuan says.

The popularity of his online videos bolsters his faith in teaching geography, which he believes can help the public gain a deeper understanding of various aspects of the world and deal with practical issues.

Practical geography was one of Yuan's postgraduate research topics, but he admits that it was not until he became a teacher that his understanding of it deepened.

To give students a good measure of the discipline's practical applications, Yuan has taken them to observe Venus transiting across the moon, and the changes in shadows around them, while explaining the reasons behind these phenomena.

"I try to encourage my students to go outside and explore the world," Yuan says.

He has also applied for access to an area at the school to grow plants and conduct other practical activities that bring the students into contact with the land, because he considers such activities crucial to learning geography.

For many students in Yuan's class, these teaching methods, like blackboard drawings and short videos, are a relaxed and novel way of learning.

Wang Mengfan, Yuan's class representative, still remembers how one short video walked her through the formation of smooth ice spheres under the force of wind and waves.

"Videos like that are like a door to a new world, where you can experience the wonders of nature in the classroom," Wang says.