OK, I gave it a shot. I hope this is what you meant...
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To fill in:
Name childs name
Action verb such as running, walking, dancing, skipping, etc.
Place such as park, cemetery, school, etc.
Thing such as bushes, car, tree, etc.
Animal
Adjective such as angry, sorry, sad, silly, etc.
It was a dark and stormy night. [Name] was out much later than usual to go [action verb] with friends. While [Name] was [action verb] past the [place], a [thing] started to shake.
[Name] stopped and looked all around but saw no one. After looking around one more time, [Name] started [action verb] once more but stopped when the [thing] moved again. [Name] said Whos there? Come out now. The only answer was No one.
Now [Name] was getting mad and said Whoever is out there better watch out or youll be [adjective]. Again, [Name] just heard No one.
Finally, [Name] decided to keep [action verb] and ignore the noise if it came again. [Name] was almost past the [place] when the [thing] shook. You better leave go away whoever you are said [Name] but No one was all that was heard in reply.
Feeling more [adjective] then scared, [Name] stopped and looked around again. Just as [Name] was ready to leave, a little [animal] ran from behind the [thing]. Minutes later, [Name]s neighbor walked up.
She asked Have you seen my [animal]? Ive been calling and calling but cant find him.
Whats his name? asked [Name].
No One was all her neighbor said.
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Seems kind of lame to me but I wasn't sure how "spooky" you'd want it to be for 4th graders so I tried to add a "twist" at the end.