Susan Simmons can tell that her new substitute teacher is really weird. But she doesn't know how weird until she catches him peeling off his face-- and she realizes that "Mr. Smith" is really an alien!

At first no one will believe her-- except Peter Thompson, the class brain. When Peter and Susan discover Mr. Smith's horrible plans for their classmates, they know they have to act fast. Only they can get rid of their extra-terrestrial visitor-- and save the rest of the sixth grade class from a fate worse than math tests!

This book is the winner of numerous awards. It was recognised in the Grades 3-5 category by the Pennsylvania Young Reader's Choice Award. It was recognised in the Grades 4-6 category by the Nutmeg Book Award. It also was recognised in the Intermediate category by the Nevada Young Readers' Award.

This book is part of a book series called My Teacher .

There are 123 pages in this book. This book was published 1990 by Simon & Schuster .

BRUCE COVILLE is the bestselling author of dozens of books, including the enormously popular Magic Shop Books, Thor's Wedding Day, and The Monsters of Morley Manor.