Colin McNaughton, in his new book Don't Step on the Crack! (Collins Children's Books pound;9.99) has some of the answers. This serious journey into childhood preoccupation and superstition is conveyed with his usual comic flair.A nerdy-looking boy, walking along the street, is suddenly beset by anxiety. If he steps on that crack (but which one? - that's the problem), the consequences will be dire: he might run into the bully boys; his baby brother might turn monstrous; he might forget to put his pants on when he goes to school; his mum might turn trendy; he might even turn into Preston Pig. McNaughton's images are pared to the bare essentials - stark, bold and very, very funny.