Several hundred French teenagers have erected barricades outside their schools and marched through Paris to protest at the police expulsions of immigrant families - including some of their classmates.
Police sprayed tear gas at a few students throwing missiles but most marched peacefully, some climbing on bus shelters to shout demands for the interior minister's resignation.
Anger erupted this week over the treatment of a 15-year-old Kosovar girl detained in front of classmates on a field trip. The government says her eight-member family had been denied asylum and was no longer allowed to stay in France.
Such expulsions occur regularly around France as the government tries to limit illegal immigration. But the treatment of the girl touched a nerve, with critics saying police went too far and betrayed France's image as a champion of human rights.
The students say the expulsions are unfair to children and hope to pressure France's Socialist-led government to allow the girl and a recently expelled Armenian boy to return to France.
At one secondary school in Paris, students piled green rubbish bins in front of the entrance and hung a banner saying "Education in Danger."
"Everybody should have a chance. Everybody should have a job, work and have a family. When children try to achieve that, France refuses, and that is not my country," said protester Romain Desprez.
The protesters tried to march to the Interior Ministry, but were blocked by riot police with shields and helmets. They diverted the march and dispersed peacefully.
The Kosovar girl, Leonarda Dibrani, said from the northern Kosovo city of Mitrovica that she wants to return to France. Activists say her family fled Kosovo about five years ago because they are Roma, or Gypsies, and faced discrimination and few opportunities.
"My home is in France," Ms Dibrani said in French. "I don't speak the language here and I don't know anyone. I just want to go back to France and forget everything that happened."
The French government launched an investigation into her detention, and is expected to announce the results on Friday.