Mademoiselle C is a strange but touching woman. She, among others excentricities, talks to a small rock, Gertrude, like if she was alive. She is the supply teacher of the 6D, the worst group of St-Cécile Elementary School. When she arrives, Mademoiselle C, with her never ending imagination, will accomplish a true revolution in the elementary school and especially in the group 6D. This movie praise the right to be different and unique. It is also a movie about the happiness of reading and the power of imagination.