Mr. Yuan prepares his lessons outside a shabby classroom perched on a cliff in Zhenxiong County, Yunnan Province. Thirteen children, the offsprings of leprosy patients and refused by local schools, have to study here. The old desk and chair are the only property of the school. [Photo: www.Yunnan.cn/ by Xu Hongyi]

A vacant lot makes for the children's "playground." They seem well-adapted to their high cliff surroundings -- and certainly appear braver than the visiting journalists. [Photo: www.Yunnan.cn/ by Xu Hongyi]

There are two classes -- one for the elder children and another for the younger ones. The elders have to repeat their beginner all over again since there is no higher grade. The whole classroom is actually a 2-meter-long passageway and is always interrupted by villagers passing through. [Photo: www.Yunnan.cn/ by Xu Hongyi]

Six children are learning Chinese Pinyin following their teacher Mr. Yuan in a shabby classroom perched on a cliff in Zhenxiong County, Yunnan Province. [Photo: www.Yunnan.cn/ by Xu Hongyi]

Thirteen children, the offsprings of leprosy patients, are refused by local schools and have to study here. Their only teacher, Mr. Yuan, who was appointed to teach here three years ago, is a serious and diligent man. [Photo: www.Yunnan.cn/ by Xu Hongyi]

Six children are learning Chinese Pinyin following their teacher Mr. Yuan in a shabby classroom perched on a cliff in Zhenxiong County, Yunnan Province. [Photo: www.Yunnan.cn/ by Xu Hongyi]

A photo taken on Oct. 30, 2013, shows the cliff in Zhenxiong County, Yunnan Province where the shabby classroom is situated. Among the total of 32 villagers, there are 13 under-age children -- the eldest one is aged 15 and the youngest is seven years old. [Photo: www.Yunnan.cn/ by Xu Hongyi]

The classroom is very dark as there is no light. Villagers plant green trees to bring hope to their offsprings. [Photo: www.Yunnan.cn/ by Xu Hongyi]

Mr. Yuan has no mobile phone or notebook, and has to write down the telephone number of Doctor Wang on the wall. Wang visits them on "Children's Day" every year [Photo: www.Yunnan.cn/ by Xu Hongyi]