People rarely learn skills as an end in themselves. They learn skills so they can accomplish something they need to do or want to do. That’s as true of writing skill as it is of driving skill.
It isn’t necessary that students write about things that interest them in order for them to learn to write. It is, however, vital that they see writing can be used to communicate ideas about what does interest them.
The best models for teaching writing are teachers of complex skills such as driving, playing a musical instrument, or playing a sport. Those instructors plunge learners into hands-on activity. Drill on specific components is always in the context of the whole process.
Moreover, the instructors stick to one application until students master in. You won’t see a music teacher giving students a lesson the flute one week, a lesson on drums the next, and a lesson on violin the third week and then expecting students to be proficient at playing the trumpet. Having students write a personal narrative, a fable, a poem and a persuasive essay during the school year and then expecting them to be proficient at expository nonfiction is just about that silly.
[2/27/2014 removed link to material no longer available.]