Chen Yu gives a free history lesson to students at a middle school in Erdos, North China's Inner Mongolia autonomous region, June 11, 2012. Chen and five other postgraduates from Capital Normal University came to the school as voluntary teachers in August 2011. They wanted to spend a year doing something meaningful and supporting education in China's less developed areas. [Photo/Xinhua]

Wang Shen, a voluntary teacher plays the harmonica with a student, June 11, 2012. [Photo/Xinhua]