This Boy's Life
The writing style in Tales of a Fourth Grade Nothing is both simple and conversational. Because the story's told from the perspective of a fourth grader, Peter's language is uncomplicated and casual. It's written in the same way that a kid would talk:
I thought how great it would be if we could trade in Fudge for a nice cocker spaniel. That would solve all my problems. I'd walk him and feed him and play with him. He could even sleep on the edge of my bed at night. But of course that was wishful thinking. My brother is here to stay. And there's nothing I can do about it. (3.27)
When Peter complains about his little brother, it's obvious that he's coming at it from a kid's point of view; he's complaining in a way that a young reader would relate to. He even has daydreams about trading Fudge in for a puppy, which is a total kid move.