Pajama Party

In a bouncy, first-person narrative, eight-year-old Casey tells of her older sister's ``bad and boring'' pajama party, at which she and her guests did nothing but eat junk food, listen to loud music and spray perfume. Disgusted, Casey sells her two best friends on the idea of a ``three-girl'' pajama party. The evening is quite jolly, though observant youngsters will realize that the agenda (which includes consuming large quantities of chocolate chip cookies and dancing to records) bears a strong resemblance to the teenagers' soiree. Though Casey is nonplussed when one of her friends becomes homesick and the affair turns into a ``two-girl'' party, all ends happily. With its short chapters, substantial print size and vibrant pictures, Hest's ( The Midnight Eaters ; The Purple Coat ) and Trivas's ( Emma's Christmas ; the Fourth Floor Twins series) rewarding collaboration is a prime choice for reluctant readers. Ages 7-up. (Mar.)