I find this article on tips for evaluating your own teaching very thought provoking.Teachers are always evaluating their students, grading and assessing what the students are able to achieve. But I wonder how often teachers evaluate themselves to determine areas that need improvement. Time always changes and a teacher who evaluates himself is sure to keep up with the changing situation. Remember, "a good teacher, teaches and learns".
In my school, we have a practice of teachers visiting their colleagues classrooms to observe and give input on the teaching methods. I find this helpful because fellow teachers get to help one another to improve their teaching in a non judgmental manner.