Thoughts on teaching and being a child

I have come to realise that I do, in fact actually really enjoy teaching.  The act of showing someone how to do something and then seeing them do it for themselves and be pleased with the results is extremely rewarding.  Seeing the charge in someone when this process occurs is thrilling and beautiful. 
Sadly these occasions rarely happen as an Art teacher in my school.  I am absolutely not exaggerating when I say that I spend most of my time, perhaps 75% doing things other than teaching; report writing, phoning parents, tidying up, preparing for lessons, dealing with bad behaviour, sitting through meetings, marking and reading or writing emails to name but a few.  This can be wholly soul destroying.  Today was particularly bad, little hurts more than being told that my lessons are boring, being sworn at, shouted at and argued with, ignored and laughed at when all I want is to share my skills and knowledge, and the joy of creating. 
All this makes me cross and I hate feeling cross, doing these kind of lessons does not bring out the best in me, in fact it brings out the worst; I become nasty and shouty, frantic, anxious and panicky, it's not good for me and it is not good for the kids who do want to learn.  It makes me feel so sad.  I never knew I could become this kind of teacher. 
As a child I was so free with my creativity.  I remember being at playgroup and doing potato stamping, different shapes like stars and hearts.  I had had enough of the potato printing and started smearing my paint across the paper with the potato to make a rainbow.  The teacher told me that I was doing it wrong.
I have become this teacher.  I teach to the rules, I teach to get grades, I teach to keep the class under control.  The joy and freedom I experienced smearing paint with a potato seems to have been lost in my school and in my experience as a teacher.
I desperately want to re-capture my creative and expressive free spirit that I had as a child, I feel I am slowly working towards something with the paintings I have been doing.  They are not perfect expressions, but they are something.  They bring me hope, they remind me of who I really am.