In Yunyang county, Chongqing, 42,000 students have packed up their textbooks and left over the past decade as the number of schools has declined from 482 to 138.
The county's Jianquan township has seven schools, two of them attended by only a single student.
A situation common in the Chinese countryside, urbanization has driven families to enroll their children in bigger schools away from their hometowns.
Rural schools are being simply left behind.
Sixin Village School in remote, mountainous Jianquan is one of them. It has just a single student - fourth-grader Wu Tao, to whom Xiang Guozheng teaches all subjects on the curriculum.
When Xiang first came to the school eight years ago, it had over 100 students, and the smallest class had nine pupils. Now he's the only teacher left.
"My teaching still follows a timetable. For gym class, we do some skipping, play basketball or go for a run. I bought a CD player to play songs for Wu Tao in music class," the 58-year-old says.
Wu Tao's parents have not migrated from Jianquan and still farm in their village. But even Wu Tao may not stay long. Local policies now call for students at fifth grade or above to move to bigger schools in urban areas.
A blackboard in one of the school's classrooms still bears a drawing from 2009.
But Xiang is not put off. He says he'll keep teaching at Sixin as long as there are children who need him.