Christmas in France is celebrated mainly in a religious manner, though some secular ways of celebrating the holiday also exist.

Children put their shoes by the fireplace so Père Noël (Father Christmas) can give them gifts. Many French families also decorate their homes with Nativity Scenes depicting the birth of Jesus.

Many families attend midnight mass. Some people put additional Santons (little saints) in their nativity scenes, which are bought at special Christmas fairs before the holidays

Source: Wikipedia