By change of school, we mean change of school during the school year, if you move, if you leave or arrive. If you don't move and your child changes from « école maternelle » to « école primaire » you might not need this paper (if you're not sure, just ask a teacher).
But if you move, you will certainly need all the administrative papers you already needed for the first registration of your kid and you will also be asked to bring « un exeat » (certificat de radiation).
What's an exeat ?
It's a paper given to you by the former school of your kid. It proves you left the shcool without leaving any debts, without destroying all the books of the school, it proves your kid hasn't been fired from this school...
How can you get this exeat ?
Just go to the former school, ask the teacher of your kid or the headmaster. If your kid is in a « collège » or « lycée », go the « administration ».
Just say you're going to leave soon and need and exeat :
« Bonjour, je vais déménager et j'ai besoin d'un exeat. »
« Bonjour, je vais inscrire mon enfant dans une autre école et j'ai besoin d'un exeat ». Then give the name of you kid, the number of his class and that's it !
It's free and easy to do. You have nothing to show or to bring (except if you still haven't paid for