Chugga-Chugga Choo-Choo

First-time author Lewis and Kirk (Breakfast at the Liberty Diner) here embrace an enduring childhood fantasy--the playroom that comes alive at night--and pare it down for very young readers. A toy engineer and his son drive a train loaded with ""freight"" (actually an assortment of playthings) around a labyrinth of track laid out in a sleeping boy's bedroom. Other toys--a jack-in-the-box, a Humpty Dumpty, a trio of plush raccoons--help load and unload the cargo, or greet the train as it passes by. Lewis's brief, rhyming couplets mime a locomotive's momentum in their rhythm: "" 'Round the mountains, high and steep./ Through the valleys, low and deep."" The onomatopoeic refrain, set in playful typography, is familiar but infectious: ""Chugga-chugga/ choo-choo/ whistle blowing/ Whoooooooo! Whooooooooo!"" Kirk's dramatically shaded, panoramic paintings revel in the toys' bold shapes and colors as well as in the disparate relationships of their sizes to one another and to the environment. He gives the classic subject matter an up-to-the-minute look: his compositions have the modeled, 3D look of computer-aided art, and his surfaces a high-gloss, airbrushed smoothness. Kids will be glad to climb aboard for the ride. Ages 2-5. (May)