Do we need to limit structures to two or (typically) three structures for a story to work? Why do we have three structures and why have experts like Laurie Clarcq in recent years limited her stories to two structures?
The answer is that when a student hears too many new things in a story, he shuts down, unable to transform so much new sound into meaning. So the best stories, for level 1 classes especially, will be the ones with the fewest structures.
Of course, before starting stories, many of us spend the fall working with our verb walls and our CWB cards and questionnaires and all that stuff in order to bring the students to acquisition on certain “power” verbs, as Eric Herman has called them. We can’t start the year with stories – it won’t work in most cases.
One might ask, “What if a teacher presented more structures, like six or even more? Could they not just PQA the structures more, taking a number of days of PQA to set up the story with the six new structures in it?” I would love to answer this in the affirmative, but my answer would be no. The very fabric of TPRS/CI is made of simplicity, and there would be too many colors in that coat, and too much weaving to do, and the fabric would be too thick and rough. It is possible in theory, perhaps, but there is a reason story scripts now have two or three structures, after over twenty years of experimentation.
We can conclude that when we write story scripts for our classes we must be careful. Too many new structures and they won’t be able to understand us. Two few and the story would be boring. It’s a double edged sword.