Well, often you'll find themes like animals and nature. Second graders are starting to learn about the world around them, so stories in worksheets could be about a little bunny's journey in the forest or how a flower grows. Also, there are themes about school life like a school fair or a classroom project.
Sometimes, it might be a team of educators and illustrators working together. They combine their skills to come up with interesting stories for 1st graders in the worksheets.
There could be a story about building a sandcastle at the beach. First, the child digs the sand to make a base, then piles up more sand to form the castle shape, next adds a flag on top, and finally draws some designs on the sides. This type of story can be transformed into a worksheet where students have to arrange the steps in the correct order. They can also write a short description for each step, which helps with their writing skills as well as understanding sequences.
Fairy tales - like a story of a kind fairy helping a poor child. This kind of story in worksheets can help first graders understand kindness and good deeds. It also allows them to use their imagination.
In these worksheets, the story is often organized by having a beginning that introduces the characters and the problem or situation. The middle part builds up the story with actions and developments, and the end resolves the problem or leaves you with something to think about.
The key elements to include are characters, setting, problem, and solution. Characters are the people or animals in the story. The setting is where and when the story takes place. The problem is what the characters face, and the solution is how they solve it.