Students of grade 6 attend classes at the playground of the Chengguanzhen No.1 Primary School in Wenxian County, northwest China's Gansu Province, on June 6, 2008. Over 50 percent of the middle schools and primary schools in Gansu Province reopened till Thursday with 17,738 students restarting their schooling. The classes setting are fairly flexible on time and place according to weather conditions and other factors. [Xinhua]