Jessica

Jessica is the imaginary friend of a girl named Ruthie, whose parents constantly remind her, ``There is no Jessica.'' But Ruthie knows better, and Jessica is included in every aspect of the girl's play. Then Ruthie goes to kindergarten and, despite her parents wishes to the contrary, takes Jessica with her. It's a confusing day, and just as Ruthie's woes are about to be desperately compounded (the children have to choose real partners), a classmate introduces herself as ``Jessica.'' She becomes as close a friend to Ruthie as her imaginary namesake. The story is characteristically on target in its reflections of the inventive ways in which children play; Henkes never falters as he outlines the logic and reasoning behind Ruthie's affection for her invisible playmate. But the denouement seems hasty, especially given all the care that has led up to it. Nevertheless, Henkes's scenes of Ruthie and her two Jessicas are visions of fun (although his people do have a bit of Karen Gundersheimer and Maurice Sendak to their marching stances), and despite the ending, readers will find plenty of pleasure within these pages. Ages 5-up. (Mar.)