Confidence

As a teacher, confidence is essential when acting as a role model and an influence for youth.  If the students in your class room can tell that as a teacher you are not confident in yourself and the material being taught they are far less likely to pay attention to your lessons.  If a student has doubt in the abilities of their teacher they have no reason to take stock in what they say.  Upheld credibility as a teacher is more important than any training a teacher could receive in being an effective teacher.  No teaching technique can make any difference in students learning if the students have no desire to learn from a teacher they doubt.
How does one become more confident in themselves and the subject they're teaching?  Experience is one way to develop confidence, but for a young teacher experience is a little sparse.  To compensate for this a young inexperienced teacher has to show more energy and excitement than they would normally be comfortable showing.  Teaching sometime requires stepping outside your comfort zone in order to capture students attention and drive the point of the lesson home.