Although I don't enjoy every aspect of teaching Spanish composition, I am interested in it because of my commitment to my own writing, and to improving all of YOUR writing. I think I am doing a better job teaching it this semester than ever before, mostly because I've been able to tie it into my own personal goals. Today for class I am making a handout with the best sentences (or clusters) of two or three sentences) that I could find from all their compositions. I realized they had all improved to the point where I could include almost everyone. This is the revision of the fourth composition, and I used an idea suggested to me by the profacero blogger: can thoughts and actions ever coincide? (This turned out to be a kick-ass topic, by the way, although some students did more with it than others.)
This exercise teaches me to see the students themselves as writers (at various stages of development). I've trying to get them to define realistic goals for themselves as Spanish majors. They won't have perfect Spanish, but they should be able to write clearly, coherently, with varied vocabulary, just as they should be able to speak the language with a decent, but not perfect accent. In other words, they should be pronouncing the language correctly more or less, even if you wouldn't mistake them for native speakers. In their writing, they should be able to express their ideas, even if they continue to make some mistakes in grammar.
In class, I'm going to have them make only positive remarks about one another's sentences. Negative critique is much easier, and the composition teacher himself (me in this case) can fall into the habit of mostly pointing out things that are wrong. Praise can sound very empty when it is not specific, so I will force the students to come up with very detailed explanations of why the sentences are praiseworthy.
Models for your own writing should be realistic ones. You can learn from reading García Márquez or Borges, but you aren't going to write like them as a Spanish major. The textbook I am using has some examples written by real students, but they are mostly very bad. I am proud that my students write better than that.