La Lutte des classes

As everyone knows, children make no difference between social classes, skin colors or religions. But then why does Corentin, Paul and Sofia's nine-year-old son, only have friends like him at Bagnolet's public school? And when his friends all leave for a private school in Paris, his parents are frightened. From now on, Corentin is the only one in his class. But the only what? (HBO Europe)