I've written before about the structure of the literature selections in this curriculum, comparing that structure to the concentric circles made in a pool of water after a pebble is dropped into the center. The center is the core of this structure, with fairy tales, fables, poetry, mythology and selected children's fiction creating it. As the years pass, more layers, or concentric circles, move out from the core, adding and expanding on this core knowledge, including layers which give a child more depth and challenge in the literature they read as they are added.
So much of what is read in the upper years of this curriculum is based on the premise that the foundational works have already been read. For example, notice that the section for retellings, myths, legends and fables make up the greater part of the first 3/4 of the curriculum, leaving only the last 1/4 without it. These are part of the core and allow for the student to tackle upper level works such as 'Till We Have Faces, Faust and the trilogies by Aeschylus and Sophocles, for example, only after they have been prepared for it.
And speaking of Faust, guess why Wagner is one of the composers in Year Twelve? Because Wagner composed a symphony inspired by Faust and is titled Faust Overture. The arrangement in this curriculum is not as random as it may first appear.
Notice that longer narrative poems by Longfellow are introduced in Year Five, starting with Hiawatha and then moving to works such The Courtship of Miles Standish and Evangeline. These narrative poems introduce the student to poetry that tells a story and familiarizes her with verse that has significant length to it. This prepares him for the classic epics read in Year Eight, The Iliad and The Odyssey.
I've recently come across another good example of why this structure is so important. Only after beginning to read Idylls of the King by Alfred Lord Tennyson with both of my daughters was I made aware of how much of the Mabinogion is referenced in this book. (It is also greatly based on Malory's Le Morte d'Arthur, but a good reading of King Arthur tales will prepare a student for this side of it.)
My older daughter, having already read the Mabinogion, was able to make much deeper connections with Tennyson's work, while my younger daughter needed much explained to her. Because I felt so strongly that this was doing my younger daughter a disservice, I stopped reading it aloud and handed the book to my older daughter, who is currently finishing it independently. I knew that my younger daughter needed to read the Mabinogion for herself before we went back to Idylls of the King. Her core must be developed before reading it; otherwise much of the literary allusions, full meaning and emotional attachment to the ideas and characters in the stories will have less of an impact on her.
I immediately went back to when it is read in the curriculum and noted that I had already moved Idylls of the King to Year Nine, when the Mabinogion is to be read, so I did have it set up correctly. I then mentally noted that I will make sure that the Year Nine Literature Reading Schedule will arrange for the Mabinogion to be read in the beginning of the schedule, before getting to Idylls of the King, which will be scheduled in the later part of the year.