Before the bac
Remember that only school exchanges arranged by the head teacher will ensure your diploma is recognised on your return, so your best bet is to participate in a school exchange or sign up to a programme, especially if you are a minor. You can take ‘National Education certified’ classes at around 500 middle and secondary schools in over 130 countries. See the AEFE (Teaching French Abroad Agency) : www.aefe.fr
A school year abroad (or in some cases a term or semester) will totally immerse you in the destination country and makes a great opportunity to improve your language skills, but this experience can be costly and is not recognised by the National Education department on your return in France. You will have to continue your schooling at the point you left as their is no equivalence in place in collèges or lycées in France. Aimed in priority at lycée students who want to take standard schooling in another country and stay with a family as part of an educational and language stay.
The international baccalaureate (IB) is not recognised in France and is supported by an educational foundation implementing curricula in 140 schools and institutions around the world. It’s recommended, therefore, that you enrol in a French lycée abroad to earn your French bac or sit the European bac or even the binational bac recognised in both France and overseas (French-German AbiBac, French-Spanish BachiBac and French-Italian Esa Bac).
In France, research the European or international sections in public or private collèges and lycées that promote international educational mobility.