This is clear from the following clues:
* Her perspective: The narrator's childish understanding of the world and her limited life experiences are central to the story.
* Her actions: She behaves in ways that are typical of a child, such as being easily upset and struggling to understand complex emotions.
* The setting: The story takes place during the Great Depression, and the narrator mentions going to school, which suggests she is of school age.
While the exact age is not stated explicitly, the details of the story strongly suggest that the narrator is around 10 years old, a pivotal time in her life.