One of the key characters in The Class (Entre les murs), the recent film that portrayed a teacher's turbulent year with a multicultural class at an inner-city Paris school, is a shy Chinese boy named Wei.
While his classmates are disruptive, Wei is hard-working and co-operative. But his teachers grow concerned that he is going to be deported with his family as "sans-papiers", illegal immigrants.
We are not told the fate of Wei and his parents, but they represent the plight of countless families with children in French schools frightened of expulsion, after living and working here for years. According to the support network Reseau Education sans Frontieres (RESF), the threat is growing as the government raises its deportation quotas.
"Problems have increased, and so have the fears of people and children. Teachers are well placed to see the damage to children and their parents' condition," says Pierre Cordelier of RESF. For years he taught at a school near the one featured in The Class. "I talk to small children. There are no words to explain to kids why they're growing up in a climate of malaise," he said.
It was hard for them to socialise, because their parents were not the same as those of their French friends, and it affected their mental health, he added.
RESF campaigns on behalf of the sans-papiers out of a sense of justice and solidarity, but there is also a legal aspect to members' commitment to change immigration regulations and practices. "France has signed the Human Rights Declaration, the Children's Rights Convention - we are bound to give asylum. There are fundamental texts we must respect which define the rights of each human being," says Mr Cordelier. The network says French immigration policy leads to "disastrous consequences for foreign children" and violates the United Nations Convention on the Rights of the Child. In evidence presented in February to the UN High Commissioner for Human Rights, it describes how - despite families' rights under the convention to live together - young children are separated from their parents, often to facilitate deportation, or locked up alone in detention centres.
Under the law, all children of school age are entitled to education, whatever their family circumstances. But registering children at school is "one of the best ways of locating and arresting parents," and police "do not hesitate to grab children inside the school," says RESF. Youngsters educated in France find when they turn 18 and apply for residence permits, they are served with a notice to quit the country now they are no longer minors.
But anger is growing. Under French law those caught helping illegal immigrants, including teachers, face a maximum fine of Pounds 27,000. Yet, earlier this month, 5,500 French citizens symbolically declared themselves lawbreakers by publicly admitting this and demonstrating outside courts and police stations.
And a new film, Welcome by Philippe Lioret, which highlights the dangers for sans-papiers, has just opened in French cinemas.