Students paint on a 100-meter-long scroll at the Anhe Campus of Zhonghe Middle School in Chengdu, southwest China’s Sichuan Province, yesterday during an event marking the world’s 57th Earth Day, which falls on today. Similar events have been held nationwide to encourage people to cherish nature and safeguard a beautiful China. First observed in 1970, Earth Day has grown into the world’s largest civic observance, now celebrated in 193 countries.Xinhua