With big, loosely drawn color-pencil sketches, Jarrett lays out a minimal but tempting playscape: a seemingly deserted park that sprouts large and delightful friends for a solitary lad to romp with while his unflappable mother lays out a picnic. Young readers will envy Jack when a giraffe, an elephant, a leopard, and a tiger appear in response to his lonely plaint. Each politely accepts his invitation to sup later, but as for now, “let’s play!” Jarrett fills her repeating, cumulative tale with words that are fun to say aloud—“Leopard went lollopy lollopy, and Elephant went tootley-toot-toot, and Giraffe went gallopy, gallopy behind them”—and ends, after a hearty meal of “hot dogs, pizza, chocolate milk, and strawberries,” with fond good-bye waves all round. Would that every visit to the park could feature such a satisfying rumpus. (Picture book. 3-6)