In a new adventure for Gus and Grandpa, the author-illustrator duo (Gus and Grandpa and the Two-Wheeled Bike, 1999, etc.) takes readers along as Gus prepares for second-grade show-and-tell, which promises to be a far cry from his fun presentations last year, when he could bring whatever he wished. This year, the teacher has sent home a list of topics. For the first topic, Mom and Dad offer suggestions, but Gus rejects their ideas only to see other kids using them come presentation time—and Ryan Mason outshining everyone. Grandpa’s suggestion of a balloon for solids, liquids, and gases, the second topic, sounds all right, till Gus gets to school: a bunch of kids have the same idea, and “almost everyone else had rocks,” except for Ryan Mason, of course, who made a gas using vinegar and baking soda to inflate a balloon. Grandpa knows a lot of Colorado history, the third topic, but Gus can’t take Grandpa’s crackly old photographs to school . . . or can he? His show-and-tell Grandpa knocks the socks off Ryan’s next presentation and restores Gus’s faith in life’s ultimate fairness. Stock’s watercolor illustrations complement and separate blocks of beginning-to-read text, doing everything they should do in a book for this readership. Together, words and pictures are an enjoyable take on an age-appropriate issue. Gus and Grandpa are a great intergenerational team; they’re lucky to have each other—and readers are lucky to have them. (Fiction. 6-8)