The cover blurbs lead one to expect a thriller of some sort - think Class Trip. If this is your expectation expect to be disappointed. One can be a third of the way through the book and still have little tension causing you to read until 3 a.m. - my test for a good thriller or mystery. And unlike The Class Trip, School's Out will not lead you towards understanding of an individual's aberrant behavior. Rather the strength of School's Out is philosophical and group oriented. Through the rather detailed exploration of the personalities of individuals who must deal with middle school class, the book explore how individuals and groups cope with "reality" - especially the adult coping through becoming an observer, the middle school class coping through uniform compliance. Suicide, physical assault, and other "thriller" plot elements counterbalance the philosophic bent to create a very enjoyable read.
On the down side, the translation is at times awkward. I would like to explain the difficulties away by claiming British usage but phrase such as "two crew" rather than "two crew members" disrupt one's reading more than simple British-isms. The book could be improved by a bit of editing - in the early part of the book the scene setting is overly long for its narrative function. But Dufosse is definitely an author worth watching - entertaining and thought-provoking.