But Liu was a rather shy, reluctant performer. Zhao said when he wanted to sing he always hid behind trees. She realized it would take some effort to lure him out of his shell. Her first goal was to get him to sing in front of the class. Once that hurdle was cleared, and Liu felt confident to sing away from the safety of trees, he performed at the school party.

Zhao's incremental approach paid off, and Liu began to take part in singing contests. In 2004, he ranked as one of the top ten singers at a local Karaoke contest.

Liu was part of a group that toured the major supermarkets in Xi'an, the capital city of northwest China's Shaanxi Province. Zhao, a newlywed at the time, decided to accompany her student at each competition. "He needed my encouragement to keep confident," she said.

Liu's talent got him into college and set a strong example for his schoolmates. Soon more and more students became interested in music and singing.

"Liu also proved there's another way to discover special-education children's potential. Parents kept sending their children in and hoped they could repeat Liu's success," Zhao said. "And more and more students dared to sing aloud while listening to their MP3 players."

For Zhao, her career in special education is more than a job – it's a self-fulfilling life endeavor.

"Every time I receive my students' sincere gratitude – not only on Teachers' Day – I feel fulfilled."