The weekend is usually a period of time for resting. But today's Chinese students can hardly rest during the weekend. According to a survey, 25%of the Grade 8 students in Beijing have classes on the weekend. Over 38% of the middle school students have less than eight hours' sleep, because of the hard study. Nan Weitong is a Grade7 student in Hubei. The girl has to get up at 6:30 am on Saturday. Then she has a whole day of classes. On Sunday, she has classes for math and English. She says her classmates all work very hard. However, some students are much luckier. They don't have to go to school on weekends. Zhang Qian, a Grade 9 student from Jinan, is one of them. On the weekend, she usually gets up at 8:00am. Then she spends some time on her homework. After that, she goes shopping or watches TV. Zhang Qian said her mother once wanted her to try extra classes. "But my teacher said it was unnecessary. Learning well at school is enough," Zhang Qian said, "I feel pretty lucky." There are   _   of the Grade 8 students in Beijing have classes on the weekend.
25% 38% 50% 75%