"Yo ho, yo ho, it's off to the bath we go!" shout the titular budding buccaneer brothers. Their mother, no fool, plays right along: "Walk the plank!" she orders her now-naked (except for pirate headgear) charges, pointing to the frothy tub. Working in the thick, color-saturated acrylics of his previous book Baghead, Krosoczka stretches the watery playground across the gutter, and makes the bubbly tub's surface as wavy and wild as the high seas. The bathers themselves embody the snips-and-snails-and-puppy-dog-tails definition of boy, their oversize heads sporting ear-to-ear grins. They jubilantly spout pirate lingo, while their sidekick, a menacing teeth-baring, eye patch-sporting rubber ducky, looks on. A hair wash by the "mommy pirate" doesn't strike the boys as worthy of two hardened sea rovers ("Blimey!" they grimace), but they carry out the rest of their bathing duties with swashbuckling aplomb, then scamper into the kitchen to claim their treasure: ice cream, eaten straight from the container. Ages 2-5. (Mar.)