Whoever said, "Those who can do, those who can't, teach." ought to be shot and mounted on a wall with a plaque declaiming "Judgmental Idiot". As someone who have been involved in the teaching industry for nearly eight years, let me tell you: teaching is not for the faint hearted.
It takes a lot of hard work, courage, determination, ingenuity and patience to be a good teacher; whether you teach pre-schoolers or university students, science or arts. You think it's easy to face 20-odd students and try to impart knowledge to them with your heart in your throat and cold sweat running down your back? It's facing stage fright every single day. Not just surviving it, but flourishing through it.
You gotta have passion for it. Respect and real appreciation for the students; be it the class sloth who sleeps everyday in your class, the slow one who doesn't seem to grasp the concept after you explained it for the dozenth time and the star who outpaced everyone including you. In my experience, the best part of teaching is when you see the lightbulb go off in their head and you know that they will carry whatever it was you showed them when they walk out. How long it stays in their head, doesn't matter, even if they lose it right after the exam result comes out.
The Schulich School of Engineering of the University of Calgary came up with Iron Science, a challenge celebrating science teachers, which is loosely based on Iron Chef, the Japanese cooking television series. I don't know how well this helps to improve science education in Canada, but it sure is a fantastic way to acknowledge science teachers and their creativity.
There is a reason why people keep making movies about teachers. Think about it.