Fifth grader Josh Hewitt rushes through life, talking constantly. People are always telling him to wait, to focus on the task at hand, to be quiet. But Josh can’t be quiet about the five-legged frog he found in his patio pool. He fights with a friend who calls it “Freaky Froggy.” When it dies, he feels responsible. There are tadpoles in a vernal pond nearby, and he worries they too might develop weirdly. He also worries about his biological father: Was he as talkative as Josh, and was that why his mother left the man? Does she hate Josh too? The pace and constantly changing focus of this third-person narrative mirror the impulsive nature of the sympathetic main character. School scenes are realistic, and the debut novelist effectively introduces current concerns and some theories about malformed amphibians. Pederson’s occasional sketches illustrate high points. Middle-graders will celebrate as Josh learns to use his personal “pause” button to stop talking long enough to keep out of trouble. Obvious appeal, particularly to fans of Andrew Clements’s work. (Fiction. 8-12)