Final answer:
Scout says 'The second grade was grim' because she had a negative and disappointing experience during that school year, as typical of literary expressions of struggling or feeling disenfranchised.
Step-by-step explanation:
Scout, the protagonist in To Kill a Mockingbird, refers to her second grade experience as 'grim' because she had a bad experience in the second grade. This statement is indicative of her feeling disenfranchised or disappointed with what happened during that year. Often in literature, when a character describes a period of time as grim, it's an expression of their negative emotions or struggles they faced during that time. It's less about the lack of detail or the potential for future events, and more a reflection on the personal challenges she endured.