I been writing about your question on my blog Artful Innovation (October 24 and 26 posts) and plan to continue exploring this question in future entries. Teaching kids to be creative (as defined by those seeking profits and economic competitiveness from creativity) is a hot topic today in education today in the U.S. because of Daniel Pink's book A Whole New Mind, Thomas Friedman's The World Is Flat, and the work of the Partnership for 21st Century Skills.
I think you are right that the creativity of teachers should be the starting point, and the first step should be looking at the school and system environment. Just about all of the books on creativity address space and culture. It's more about nurturing or even just not stifling creativity than it is about learning creativity techniques. We have a long way to go just with cultivating the environment. Diverse perspectives—whether from interdisciplinary projects or teaming with people outside of the school—also will teach creativity. And finally, I think it's about tasks. Develop engaging, motivating tasks that call forth the creativity and innovative capacities students already have and drive them to experiment.