When the principal tells Mrs. Toggle that her new student will be a dinosaur, she is taken aback but doesn't doubt his word—Mr. Stickler never jokes. Mrs. Toggle and her wide-eyed class start to get ready: they'll need a big desk and another reptile to keep the dinosaur company; the cafeteria should be warned. As the avid class troops from library to kitchen, doing research and making plans, a green diplodocus grows in their imaginations—and in Alley's engaging cartoon-style illustrations, which deftly capture the kids' waxing enthusiasm. Then the new girl arrives: Dina Sawyer. Though the dinosaur fades out of the picture, the children have enjoyed some unusually well-motivated research and considered the meaning of welcome in a unique context. A fine sequel to the equally delightful Mrs. Toggle's Zipper (1990). (Picture book. 4-8)