Passen once again mines B-grade monster movies, as Irma Birnbaum—dubbed “the toughest teacher in town,” but “most obsessive” would be more like it—undergoes a third form- and character-altering transformation. School’s closed by snow, but Miss Birnbaum skis out to deliver homework, declaring, “I cannot let a day of education be wasted!” Not even a zap of electricity that turns her into a hairy monster stops her from assailing terrified children with test questions—until a mysterious whirlwind and a second zap cause her to lighten up. And, happily, shed the pelt. Portrayed as a formidable figure in pointy glasses and a towering gray beehive, Miss Birnbaum makes an intimidating figure even without the fur and paws. Her cheery closing proposal that the class build a snow fort rather than crack the books makes an object lesson in deceptive appearances—but Passen is recycling the same basic plotline, and children who have already met Miss Birnbaum in her previous incarnations may find it growing stale. (Picture book. 6-8)