Here's a breakdown:
* "Devoir" means "assignment" or "homework"
* "de" is the preposition "of"
* "français" means "French"
You can also use other variations depending on the context:
* "Travaux de français" (French work)
* "Exercice de français" (French exercise)
* "Tâche de français" (French task)
The best choice will depend on the specific type of assignment.