You were called to account for a misdeed. Readers question your perspective in this sentence:

Baffled by the exaggerated severity assigned to my minor indiscretion, I had hoped for acknowledgment of my dedication to reading during the holidays,

What seems like a minor indiscretion to a young student is hardly that. This was a complicated scheme to use the books in the library in a way that was not allowed. Readers are inclined to agree with the school administrator. Even though your intention was to return the books, you did take them and use them and could have potentially harmed them.

You tell this story well. You describe your feelings at each phase of this experience. You us dialog well. All in all, it is a very well-written piece.

Thank you for sharing this with us, @zyzymena