I have recently finished Constance Weaver’s 1996 book Teaching Grammar in Context (purchase from Amazon). While I agree a great deal with Weaver’s arguments and hope to implement many of her ideas in my own classroom, I would like to see more studies on the efficacy of her methods. In many schools, the curriculum dictates teaching grammar in isolation, at least part of the time, and my experience at a private school, has been that many of my students had a good grasp of concepts taught in isolation. They did not, however, consisently implement the things they learned or that we reviewed in their writing.
I found the section on the history of the teaching of grammar very interesting, and I might share that with students. All in all, I highly recommend this book to English language arts teachers at all levels.