If any picture-book moral would seem to be done to its death, it's the one that the star-covered witch frog delivers to mongoose Marie Louise and her snake friend Christophe at the end of their latest escapade: ""Let that be a lesson to you not to try to be something else."" But the path Carlson takes to that conclusion is all her own, and chosen, it's clear, strictly for the delights en route. Early on Marie Louise and Christophe see preparations for a carnival, which they'd like to attend if only the people wouldn't throw sticks and stones at them. So they ask the witch frog to turn them into humans for the day. Well, that's beyond the witch frog's powers, but he can turn Christophe into a rope by rubbing him with mud--the magic will be lost if he moves when anyone is looking--and turn Marie Louise into a cat by putting a cat-head-shaped gourd on her head. ""But you must keep saying the magic word aloud."" The magic word is MEOW. Well, for a time the two are so successful that Marie Louise is about to be awarded a prize for her cat costume. But Christophe wants a prize too--and so the two are discovered and chased off with sticks and stones. The moral, then, is both a surprise and a consistent bit of ingenuity from a very canny witch--quite in line with this pair's bright, enticing mischief.