You
The poem is written in the second person, so that the protagonist is identified with the pronoun "you." This has several important effects. One of them is that it reveals the passage of time and sheds light on the speaker's mental state. The speaker appears to be describing her own childhood. However, the word "you" implies at the same time that she is addressing someone else. This creates a distance between two versions of the speaker—the one doing the speaking, and the one in the childhood memories. The second-person point of view, in other words, demonstrates the way that time has made the adult speaker into an almost entirely different person from her childhood self. Moreover, because "you" can be singular or plural, it isn't always clear whether the poem is describing a single person's experiences or those of Mrs. Tilscher's students in general. This reflects Mrs. Tilscher's impact: her nurturing persona creates a community, but also makes each student feel safe and respected.
Mrs. Tilscher
Mrs. Tilscher is a figure of outsize importance in the speaker's memory—an adult teacher so skilled and kind that she successfully keeps fear and boredom at bay. Mrs. Tilscher's classroom is a realm unto itself, which the teacher fills with near-fantastical experiences: vivid descriptions of faraway continents or amazing natural transformations. The teacher makes the students feel important and valued with small but impactful gestures, like placing gold star stickers next to their names. Her classroom is more exciting than the children's homes, and it's also more secure, so that frightening current events or popular culture can't disturb its peace. However, even Mrs. Tilscher can't prevent the children from growing up. She has the power to make their childhoods better, but not to prevent them from becoming adults.
The Rough Boy
The "rough boy" is a catalyst for the speaker's transition to adulthood. He explains the concept of sex to the speaker, igniting a series of irreversible (if inevitable) events. The speaker is upset by what the boy says, and reacts by kicking him. Still, she can't ignore what he has said. She finds herself looking differently at her own parents. Later, she asks Mrs. Tilscher herself about what the boy has said. When she leaves Mrs. Tilscher's class, this new, adult knowledge lurks just on the edges of her consciousness. The boy's boldness makes him the first person to explain this element of adulthood to the speaker.
