This is quite a tall tale with a cute "pet" as the result. I enjoyed the imagery brought about by your tale-telling of the location, scene, and scenery. One of the metaphors I especially appreciated was referring to a particularly tall junk pile in the back yard as "the Appalachia of crap his daddy had built." That paints a picture of the people and the atmosphere as well as the piles in the back yard, and I love that you get so much from that one phrase.

I went back and forth with myself on one point: the title and fateful line: "The Earth exploded." When I read this line, I saw an image of the planet exploding. Then I saw the next line and had to dial my expectations waayy back, because not only is the Earth still whole, but Little Johnny hasn't even fallen off his precarious rusty ledge atop a haphazard pile of junk. This line does serve to give tremendous shock value, and for Little Johnny it might have seemed that the Earth exploded. Is it worth the over-the-topness? Yes, I think maybe it is.

Something I noticed throughout this story was an unevenness in your voice. By this I mean that the sound or tone of your storytelling varies widely between down-home spoken tale to almost article-specific wording that made the ride feel a little bumpy. This was more evident to me in the first half of the story than in the second half. The words you choose are obviously the culprit and make a huge difference. It's easy to see you carefully worded much of the story to give it that casual vibe. Writing that his father was dealing with a wreck "that needed some hauling" and that Johnny "hazarded a look around" gives an easy-going feel to the story. Yet mixed in are descriptive words more likely to be found in nonfiction, which creates a jarring experience for the reader.

A quick and easy word-check to show how much word choice can make a difference: if you want to give an easy feel, always refer to Little Johnny's male parent as "daddy" instead of sometimes also using "father." Same goes for "mama" instead of "mother." The difference between the two words should give you very different connotations.

In describing Johnny's game "Rock Throw" you write he would "extract one of his pre-gathered rocks" when "pull out a rock" would flow with the casual voice. It could be that the juxtaposition of the casual and scientific words add to the comedic effect which is lost on me at the moment (I do find the story funny and enjoyable), but this is just something for you to notice as you write your stories. Generally we want to keep our voice smooth and predictable so as to not pull the reader out of the story experience. I hope my mentioning this now might be helpful to you in your future writing.

I enjoyed this story, your humor, and your way with words. I think you're well on your way to writing some really fun and comical fiction. Thank you for sharing your work, and keep on writing!