Think about piano or violin. Not at all. We expect wrong notes. We expect awkward expression. But through a process of modeling, listening, practicing and reviewing specific, graded techniques, anyone can learn to play violin or piano.
Writing is similar.
Modeling when teaching art is not only effective, but absolutely necessary. They point out one or two specific areas for improvement and assign practice goals to address those problems. As one technique improves, another gains the spotlight. With this in mind, let us consider some mistakes which are so easy to make when teaching writing. This is perhaps the most common and dangerous mistake, especially for elementary and intermediate level children.