The aide à la rentrée, or ARS (Allocation de Rentrée Scolaire) enjoys an increase in line with inflation this summer meaning children aged 6 to 10 years will get €360, 11 to 14 year olds €380 and €393 for 15 to 18 year olds.
This money is to help you with the cost of equipping your child for the coming school year.
So long as you submit your tax declarations in France, you don't need to do anything to receive this money which will be paid automatically into your bank account towards the end of this month.
But remember, if your child turns 16 during the coming academic year, or is already 16, you won't get the money until after the start of term and after you have sent an attestation de scolarité to your local CAF. Your child should bring this attestation home during the first few days of term, if not, ask at the school secretariat.
Your entitlement to this grant is based on your 2011 income, as declared on your 2012 tax returns.
To find out more about education grants see http://www.kidsinfrance.com/2012/02/education-grants.html