As night falls in Beijing, yuppies descend upon the sassy Sanlitun Bar Street in Chaoyang District. Like a parade of dark angels, each one of them is dressed to kill. A mug of beer here costs about $4.

Chen Dan, 6, lives 30 minutes away, but has never heard of Sanlitun. That mug of beer would buy her a month's lunches, a week's bus fares and several days at the "school for children of migrant workers."

The story of Chen Dan is told by the Chinese author Huang Chuanhui in his book, "Where's My School Desk?" Like millions of other children scattered around Beijing and other Chinese cities, Chen Dan is a "floating child."

She lives with her grandparents, who migrated from Hebei province to work as janitors for the public toilets that litter Beijing. Their home is actually one of those toilets - a makeshift shed of broken bricks and discarded blankets piled at the back of the facility. They make about $40 a month.

There are an estimated 140 million such "rural migrants" working in China's cities as janitors, laborers, street vendors and at other jobs shunned by city dwellers. The children of this "floating population" are China's "floating children."

Chen Dan walks an hour each day to school. Except it is not so much a school as a makeshift childcare facility for migrant children, unregulated and unrecognized by the city government. During her breaks, she gathers old bottles for recycling to help pay for her schooling.

Still, she is lucky, because many migrant children in China get no schooling at all. Public schools in Beijing serve only local residents, so migrant workers who cannot enroll their children pay a hefty "education leasing fee" - often the equivalent of a year's earnings.

As a result, most "floating children" do not attend school, wasting their days playing in the dust with scant hope of someday climbing the social ladder.

At one point, some people, mostly retired rural teachers, took the initiative to organize informal classes for these children. These "schools for children of migrant workers" mushroomed throughout the cities. But because they have no legal status, they are often closed down by the city government.

So who should provide for the floating children? The problem is both fiscal and administrative.

On the fiscal side, China is unusual in its extensive decentralization of the provision of public services. In 2004, local governments were responsible for 72 percent of total public spending. Basic services like education and health care are almost entirely the financial responsibility of local governments.

The result is that local governments will only provide services to those who pay taxes directly to local coffers - legal, local residents.

Migrants have to pay additional fees to enroll their children in public schools because they are "leasing" a public service from a "foreign" government.

On the administrative side, the Chinese government has for a long time debated whether to abolish the cumbersome household registration system.

A legacy of the Maoist era, the system was intended to curb population movement by tying social welfare benefits to one's place of birth. Through the 1970s, moving away from one's home town would literally mean starvation.

But as the economy opened up, the registration system began to crack under pressure. Hundreds of millions of rural residents flooded into cities in search of opportunities.

Yet the requirements to change one's official residence, which include ownership of property and a job, are prohibitively stringent. And in Beijing, the children of poor migrants, even if they were born in the city, inherit the rural residential status of their parents.

Eleven provinces in China, including Shanghai, have changed the rules to allow rural migrants to receive the same benefits as urban residents. But this has placed tremendous strains on local finances and is at best weakly implemented.

The 2008 Summer Olympics are shaping to be one of the most glorious events in China's modern history. But for migrant workers, it spells disaster because the streets will be cleared of vendors, shacks, and makeshift schools.

Beneath the dazzling city lights and relentless clang of construction, China's floating people will have to content themselves living in the darkest of gutters.

The 'floating children', adrift in China's cities - International Herald Tribune