I have almost finished my teacher training and am considering writing my dissertation about the importance of good teacher subject knowledge. I have a good educational background and I feel confident about my knowledge but at times I am tempted to just refer to text books the week before I teach a subject I have forgotten about or a topic I haven't thought about since I was at school. I would just like to know people's thoughts on the importance of teachers subject knowledge in the classroom...
When I was training as an FE lecturer I was told that the stock response to a student question to which you didn't know the answer was "Go and look it up in the Library and report back next time." Otherwise known as FOFO (F... off & find out). They can then map it against their skills attainment.
Seriously, you can't be expected to know everything - I can't see your problem about consulting textbooks: do you write notes for your lessons and refer to them in class? I made it to Head of Faculty - it's not a crime!
I usually get the information I need and take it all with me, so I have a wealth of information. After that, the classroom computer can google other difficult areas the children want to know more about. But looking back, I have forgotten those things I researched for those lessons and would have to look up again for next time.