In this file photo issued on Feb. 10, 1990, children play a ball game at a boarding school in southwest China's Tibet Autonomous Region. As China celebrates the International Children's Day, there arises the occasion for grown-ups to think back over the joys of childhood. With the evolution of technology and lifestyle, children are exposed to a wider range of entertainment. Nevertheless, joy would remain a childhood motif no matter how its forms change with time. (Xinhua/Ma Jingqiu)