Guo Chenggang with one of his students' works. Photos by Gao Erqiang / China Daily

The courage to express themselves and willingness to communicate with others can overcome the sense of inferiority and isolation that's common in the group, Guo says.

Special art shows are regularly held to show the best work of the students.

Ye Xiufen, a mother of a mentally ill student, almost shed tears when attending an art show this March in Shanghai. A painting by her 31-year-old daughter was chosen for a public exhibition with other 35 works created by special-needs people in Xujiahui community in the city's Xuhui district.

Ye's daughter has studied painting for six months from volunteers of Guo's group, who give lessons from 9 am to 11 am every Thursday morning.

"I am really surprised by her progress. She never painted before and had never showed interest in it," Ye says.

"The painting class has improved my daughter's ability to think and observe. For example, before, she would wear whatever clothes we chose for her. Now, she has her own ideas on colors. She chooses clothes by herself and matches different shoes."

Ye credited her daughter's progress to the efforts of the "loving, caring and responsible volunteer teachers".

Wu Jiong, a volunteer teacher of Xujiahui community and a cofounder of Guo's NGO, says that she was touched and inspired by the students.