Teaching Manual

During the free time between classes on "rustlingly busy" Wednesday, our head teacher, Toshi, gave me feedback on the observation of my class.
Then, I knew it for the first time...
We (teachers) "shouldn't" bring teacher's manuals in the class!!!

If I calm down & think, it makes sense. The distance of A teacher and students is really close in my school, so, it might not fair that a teacher can bring "a book of secrets."

However...frankly speaking, it's TOUGH!!
I have 15 classes and every class is different. Different generation, different textbook, different teaching points. The methods are very similar, but "how to approach" is so different between adults and kids. Also, the school doesn't allow teachers to bring the textbooks & teaching manuals to our home.
It means... We should prepare for a long time at school (but we have other things to do!!) and...we should VERY fluent in English & understand EVERYTHING.
For other experienced teachers, it may be "common sense."
Wait a minute, my preceding teacher, Emily, brought teachers' manuals in her classes!!

But I shouldn't complain... It's tough, but it will be very helpful to improve in "my" English, too. Let me think so...