My Teacher is an Alien Author:Bruce Coville ISBN: 0-671-64748-2
SIXTH GRADE IS JUST ... OUT OF THIS WORLD!
Susan Simmons can tell her new substitute teacher is really weird. But she doesn't know HOW weird until she catched him peeling off his face -- and she realizes that "Mr. Smith" is really an alien!
MY TEACHER IS AN ALIEN is a book for 8-10 year olds who are eager to explore the genre of science fiction but are not ready for the totally bizarre creatures and other odd factors found in sci-fi books for older readers