The survey by the office of the Women and Children Work Committee of the State Council and the China National Children's Center, covered nearly 20,000 people in nine big cities.

    China has nearly 20 million migrant children under 18 who should receive compulsory education. But the survey found 9.3 percent of them, or about 1.86 million, have to drop out of school.

    One of them is 12-year-old Chen Qiguo, son of a migrant farmer working in Beijing.

    Since the new term began last week, Chen has stayed home because his family cannot afford tuition fees of about 300 yuan (US$36).

    Chen's father, ill in bed, was on the verge of tears when speaking of his son's education.

    "I'm sorry for my son, I couldn't send him to school," he said.

    Dong Qingyun, headmaster of the privately funded Shuren School in Haidian District of Beijing, which was set up specifically for children of migrant farm workers, said his school loses dozens of students at the start of every school year.

    Only "relatively rich" migrant workers are capable of bringing their children to city schools. Many migrant workers in construction, manufacturing and service industries dare not even think about sending their children to school.

    Zhang Qing, who came from the countryside to work in southwest China's Chongqing Municipality years ago, said sending his two sons to government schools in the city was just an extravagant hope.

    "How can I afford those extra school fees charged for students from migrant families? It's expensive," he said.

    In the Ninggong Primary School of Nanjing, in east China's Jiangsu Province, students from migrant families have to pay extra fees to studying there as well as 1,000 yuan (US$120) in so-called sponsoring fees.

    "The school has not enough classrooms and we cannot accept all children, so we have to set a high admission prerequisite," said the school office director surnamed Li.

    Because many migrant workers cannot afford the tuition fees charged by most government schools in the city, they have to send their children to private schools which are run only for them and do not charge too much.

    But most of these schools do not meet required standards. With no comfortable school houses, no qualified teachers, and even no legal licence for running a school, they are often ordered to close.

    Tuition fees are not the only obstacle for the children of migrant workers.

    They say city children bully them and look down on them.

    "My mother seldom gives me pocket money and I have no new stationery, so my classmates from the city always make fun of me and even say some dirty words," said a tearful Zhao Rongwei, who accompanied his parents to Wuxi City of Jiangsu from the countryside of east China's Shandong Province.

    "I was very sad, but I dare not tell my mother," he said.

    Some migrant farm workers do not support their children's education.

    "I get up at three o'clock every morning and go with my mother to sell vegetables in the market," a girl student wrote in an essay. "Mother says these days that it is no use for me to study and I had better help her sell vegetables, but I really want to go to school."