The Xiamen International Marathon, which will be held on Jan 3 next year, involves a charity run. Players can join by donating money to buy *virtual trees. The money will be used to plant trees in Minqin, Gansu. Usually, students need to spend 1,000 yuan buying 100 trees. But readers of 21st Century can donate 210 yuan for 21 trees. The Million Forest Program, a cooperative partner of Xiamen International Marathon, *initiated the activity.