David Grossman 
Book Of Intimate Grammar 

Eleven years old and on the cusp of puberty, Aron Kleinfeld is precocious, imaginative – the leader of his gang of friends. But his bar mitzvah is looming, his friends are all hitting puberty and Aron, terrified and revolted by what he sees around him, enters a state of arrested development. He stops growing, retreats from the world, and is imprisoned in the body of a child for three long years. While Israel inches towards the Six-Day War, and his friends cross the boundary between childhood and adolescence, Aron remains in his child’s body, spying on the changes that adulthood wreaks as, like his hero Houdini, he struggles to escape the trap of growing up.