Good young adult novel...
For unhappy Monnie Fitts and timid Bim Ross---two foster children who live with the Johnsons---finding an old, faded purple mailbox in a vacant lot was to be their secret. The seven mysterious stars painted on the door made it even more important . . . and strange. Once they wrote their names on it, life would be different, very different.
Each day, as Monnie and Bim visit the mailbox, unusual gifts and notes appear---a broom, a wand, a light---even a voo-don't doll; in all, six magical wonders that plunge them deep into a week of unexplained happenings.
Not until the seventh suspenseful day do they know where the powerful spells will lead them. Frightened, but brave, the two children enter a supernatural world to find answers only they can understand.