From January 15, for international flights and with a valid French ID Card for international travelers or valid French Passport, any unaccompanied minor or not accompanied by one of their parents must carry a travel permit. This document should be signed by both parents or legal guardians and be supported by a photocopy of a valid ID (or one that has been expired for less than 5 years) of said parents or legal guardians. For further information, contact the local French authority responsible.
The family register is not a valid identity document for French citizens who are minors. Therefore, minors are not permitted to fly on planes, even within continental France, without a National ID.