Oranges: a fruit, also a color. The Narrator most likely has strong feelings, whether good or bad, toward it.
It is cold outside. The Narrator (N) is walking to meet a girl. It is the first girl they have walked with. N is 12. They have two oranges in their pocket. As N meets up with the girl a dog barks at them. N and the girl walk to the drugstore. The girl wants chocolate the cost 10 cents but N only has 5. They pay with the nickel and an orange. They walk for a bit then break to unwrap the chocolate and peel the orange. It seems to glow.
Blithe: First time, yellow, bright, smiled, newly planted, candies, light, chocolate, fire Melancholy: Cold, weighted down, cracking, used, drugstore, narrow, didn't say anything, quietly, old, gray Tone: Bittersweet, the narrator is remembering a time that was happy, yet it seems as if there is an air of sadness around the memory.
In the poem, the shift happens when the first stanza ends and the second begins. It changes from being a sad and happy sounding memory to a hopeful one tinged with sadness.
Oranges: a fruit that represents, and possibly triggers, this memory of the Narrator.
There are two themes in this poem. One is trading things you cherish for the ones you cherish. The second theme is bittersweet memories.