To the likely delight of small children everywhere, Andreae (Giraffes Can't Dance) moves beyond "I See London, I See France" for a bouncy rhyme about underpants. From "giant frilly pig pants" to "cheeky little monkey pants," with many wacky (and perhaps familiar) styles in between, the snappy collection of garments will elicit plenty of giggles. Sharratt (Do Knights Take Naps?) reinforces the sense of fun with a series of gleeful, boldly outlined images in an electric palette. Elephants, zebras and kids alike sport snazzy knickers throughout. In addition to their lightness and humor, both text and art provide ample opportunity for kids to practice concepts like color, size and shape identification, and counting. This exuberant paper-over-board book may even be a help to parents and caregivers who are introducing the potty-training concept to their diaper-wearing charges. Ages 3-6. (Aug.)