Unlike Wiesner's, these frogs have a motive for their journey, their pond--in any case contaminated with litter--is to be bulldozed. Loading their tadpoles into a jar, they set out to find a new home, traveling over a city bridge and through a sewer, evading a cat and rats, and hopping through a restaurant full of surprised diners before settling in a pretty pond surrounded by flowers. Comparisons are inevitable, and perhaps unfair: Tuesday's frogs have a unique surreal charm. Still, the Snapes' are beautifully observed, realistic yet imbued with real character; and while their ""odyssey"" includes some lapses in logic (how does a frog climb a streetlight?), the visual narration is engaging and the ecological message effective.