"After all, the children have been in the school since they were 5," she said.

Enrolling in a public school requires parents to submit a series of certificates, such as a temporary residence permit and a certificate of employment, which can be difficult for migrant workers to acquire.

Tang Siping, principal of the Zhenxing School in Haidian district in Beijing, said the district's education authority is doing all they can to help the migrant workers' children.

"The government authorized two private schools for migrant workers' children, so some children who cannot enroll in public schools, for reasons such as their parents cannot gather all the certification needed, can go to the private schools," Tang said. Zhenxing School is one of the authorized schools. It currently has 1,500 students.

Although the education authority provides some financial support to the authorized schools, Tang said it is not enough.

"The government subsidy only covers the school's facilities, but does not include the expenses of the faculty. And we cannot charge the parents because that would make it unaffordable for them," Tang said.

The school has more than 50 teachers; the wages alone cost 100,000 yuan ($16,090) per month. And the school did not buy social insurance for teachers until this year, after receiving a donation from a foundation.

"The money is enough to pay three years' social insurance for the teachers. But after that, I do not know where else to find that money."

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