Here is a posting from one of my new (to me anyway) favorite blogs:

I write this not as a skeptic of the value of thinking about pedagogy and of improving one’s teaching–but, and level with me, dear readers–isn’t that what we do all of the time, throughout the year, without going to workshops or special “colleges?” Isn’t this what we do, when we assign all or mostly new books to our classes each term, so that we can keep up with the current literature in our fields (and not incidentally, avoid boring ourselves with the same old readings)? Isn’t this what we do when reviewing previous drafts of lecture notes to see what’s outdated or less useful, and to add new material based on your current readings and research, or to speak to the specific themes we;re emphasizing in this or that semester? Aren’t we always adding new visual images, new ideas, and new slides to our PowerPoint lectures? Do any of us set out intentionally to bore our students to death? Do we enjoy being out-of-date and out-to-lunch in public?

I remember hearing about that legendary college professor who worked from yellowed note cards, or off of lecture notes on legal paper from the 1930s that hadn’t been revised since they were first drafted. Remember him? Me neither. I never met that guy or took his class–it was always someone’s brother’s roommate, or someone’s girlfriend’s sister who was in that class, and usually at another college or university. That professor is largely an urban legend, but “Centers for Teaching and Learning” are set up and funded to guard against him in universities across the country. (Do they also sponsor a “Center for Defense Against Unicorn Attack?”)

Yes she's writing about college but easily adaptable to any teacher's situation.