On June 20, 2013, an estimated 600 thousand school children and their teachers across China watched a science lesson taught from 300km above the Earth by astronaut Wang Yaping. Wang is aboard the Tiangong-1 laboratory module with two crewmates, for a two-week mission. Her lessons were a series of physics demonstrations in the space. In some demonstrations,she compared with the same experiment under the one-gravity environment on Earth. The lesson has not only offered children a physics lesson with knowledge and interest, but also shows the advance in communication technology of China.