We spend so much time talking in composition classes about writing as process, I often choose to start the semester with the notion that writing is valuable as artifact as well. Here are a few examples from the family archive:
This is, of course, a proto-document from early childhood (when my oldest daughter was maybe age three and a half): the letter to Santa Claus. Unfortunately, I've lost my ability to decode this fully, but I can make out a few words (people, very much) and, I think, most of the closing (by the way, say hello to the elves from me). Relevant topics: audience awareness, exigency, formal conventions dictated by genre, written vs spoken language (as in, usefulness of inter-word spacing)