Readers of French may like a humourous children's book written by Estelle Demontrond-Box, who translated "The Green Man" for me.  It tackles the subject of bullying and is aimed at 9-12 year olds.  It's called "Le Pacted des Bouffons":-

It's available both as a paperback or an electronic download, and you can get 25% off if you order before 31 January 2012 using this code:- LULUBOOKUK305