I don't think this meets the strict definition of elegy, but this poem was triggered by spontaneous emotion following my discovery of the story through family history research. Unusual, perhaps, is that I turned the story around and wrote it in the first person. Much later, when I found a suitable melody, it became a song.
My reason for suggesting it is that the girl in the ballad was not much older than your students. Perhaps your students will 'connect' with that.
Strange that I'd mourn the death of an ancestor, but that's exactly what I experienced. A surreal experience given that I had never before written a poem!