Gemma Warren learned that not all students will love you and, if you read poetry under your desk, you look like a wally and your skirt gets dirty.
Why do you teach? I decided to become a teacher after I watched Dead Poets Society a few too many times. That's it. There's no other reasonable explanation for it, except for the fact that Dead Poets was then reinforced by Dangerous Minds and Mr Holland's Opus.
This left me with some awkward questions to answer when I turned up at the interview for my PGCE. The inevitable "Why do you want to do it?" led to some hasty improvisation. I babbled along the lines of loving my subject and loving children, wanting to make a contribution to society and not minding about being permanently broke.
I didn't mention anything about thinking that a week with a difficult Year 11 class might give me a figure like Michelle Pfeiffer. It must have worked because I managed to get in.
Falling for the media image of teaching is one of the worst things you can do. Somewhere in the back of my mind, I naively thought that all schools looked like the stately home Robin Williams taught in.
I thought standing on chairs was the best way to recite poetry. And I thought generally sending out messages of love and enthusiasm would be enough to inspire children in my lessons.
I did once try to get my Year 10 class to sit under their chairs during a poetry lesson. They refused on the gounds that they didn't want to get their skirts dirty. So I sat like a lemon under the desk, trying to prove to them that poetry gives us a different viewpoint on life. Teaching practice is a good time to make these mistakes.
The media does strange things to teachers, especially young impressionable ones. On the one hand, you get the Hollywood fantasy of soft-focus teachers and pupils, where each day is a personal revelation and every piece of homework is handed in on time. On the other, you get the British tabloid view that every school is a murky hell-hole where teachers struggle to survive violence on a diet of drugs and drink.
Find your own niche and choose your own way. But don't beat yourself up with media images of teachers written by people who haven't set foot in a school since they left one themselves.
I've had Dead Poet moments, and I've had a few tabloid moments. Making the break in my head between the media images of teaching and what I was faced with in the classroom was an important step. It allowed me to become the kind of teacher that suited my personality and abilities. You've got to work with what you've got.
Gemma Warren teaches at the Latymer School, Edmonton, north London, and is a columnist in TES Friday magazine. This is an extract from a guide she has written for new teachers. Price: pound;2.99. Order from The TES bookshop at www.tes.co.uk or call the shop on 01454 617370