Written Narration in letter form?

The main idea is to incorporate various styles of writing as students become comfortable in written narrations. Story form would be telling the story of _____, the kind of narration we most often use. Once the student is comfortable writing in that narrative style, you can also include a challenge of writing a narration in poetry style: something like, Tell the story of _____ as a poem. You could even ask for a poem in a specific style, like free verse, haiku, etc., depending on whether the student is familiar with those kinds of poetry. Then you can also assign the student to write a narration as a letter from one character in the chapter read to another character. 

I guess the main point is that these various styles of writing can easily be incorporated in regularly scheduled narrations rather than studied and assigned as separate composition lessons. Does that help clarify a bit?