A dearth of science teachers is a common problem for the county's primary schools.

"Those who major in physics, biology and geography prefer to work in local middle schools, where there is also a shortage of such teachers. Therefore, it's not uncommon for local primary schools to train current teachers to teach science, usually covering two subjects," he says.

Li Yongping, 41, who used to be a mathematics teacher at the school, began to teach both science and mathematics four years ago. Starting from this year, he only teaches science.

In the beginning, he had to teach himself to be well-prepared for classes and conduct experiments on his own.

"You need to make a conclusion based on the experiment. If there are errors, you may end up nowhere," Li says.

Among the school's 1,620 students, over 60 percent are from rural areas.