A recent blog comment has prompted me to write this post:
I believe a way to become good at something is to teach it. You need to have confidence in what you know and understand how to explain it comprehensively. As a full-time karate instructor for many years, I have watched myself develop my martial arts in different ways as I taught more and more. I began to always make sure I practiced what I preached, and corrected myself as I would an advanced student at the dojong.
I have been teaching since I was 15--Black belt since I was 11. Age doesn't matter in the dojong; As long as you can express yourself fluently, comprehensively, and be professional, your students shouldn't care how old you are. Everyone asks my age, and I never tell. As far as their concerned I am 30 in black belt years. Young or old, anyone can be a great martial arts teacher with practice, repetition, and the will to help others.
Which leads me to my next point: Any rank can be a good teacher. I have seen white belts explain to other white belts a technique perfectly. Students have helped students with their one step sparring techniques, and even though an orange or yellow belt may be considered a beginner, it sometimes takes 2 years of experience and training to become that rank. Yes, experience matters when teaching. So does confidence, a well thought out plan for a class or a drill, and a good demeanor. An adult who has 2 years of training and has obtained the rank of yellow or green belt (8th or 7th gup) may be a parent, a teacher, or has dealt with children and adults before. They know how to deal with child's "ADHD" or an adult's probing question. As long as they now their stuff, they too can be as good of a teacher as a belt belt is.
So kudos to your instructor if they allow member of your black belt club or leaders club to teach warm-ups, kicks or punching techniques, and forms or katas. This is good practice for the student and for their future. And, it's certainly a reflection of their instructors as well :-)