Knee-high hams have few published plays to choose from. These first appeared in Humpty Dumpty magazine. Each has three or four characters and is uniformly short and to the point while underlining a moral about behavior or emphasizing a virtue. The dialogue is in an easy-to-read vocabulary. Judith Martin, the founder and co-producer of The Paper Bag players, provides the introduction in which she points out that a special stage and equipment are not needed to satisfy young actors or their audiences. The important feature of the book for people trying to direct the youngest (the plays seem best suited to nursery school through first grade) are the illustrations by Ilse-Margret Vogel. These show very clearly and cleverly how to adapt the simplest items to stage props and costumes. For instance, a cardboard box can be a handsome rooster costume with the judicious use of frayed paper and paper bags can be turned into almost anything. Interesting and very useful.