Paul Zindel has been a trendsetter in young-adult fiction since 1968. Significantly, his latest book ["The Undertaker's Gone Bananas"] features a teen-age girl who's obsessed with death, a boy who's obsessed with practical jokes and an undertaker who's a homicidal maniac. Significantly, too, Mr. Zindel turns these elements into a zany farce…. The most striking feature of Mr. Zindel's story is the setting—a white elephant luxury-apartment complex on the Palisades Cliffs. The tenants, mostly refugees from other urban nightmares, are surrounded by unrented and perhaps unrentable apartments, and Mr. Zindel's hero [Bobby Perkins], who can't get anyone to believe that he has witnessed a murder on his neighbor's terrace, is the most isolated of all. This book is like a screenplay waiting to happen. The imagery is terrific, but, I confess, I'm not sure what the images mean. Do today's young people really feel so bereft and abandoned...