For this to make any sense I need to tell you a bit about myself. I'm 27, female, 5ft 7in, with green eyes, blonde hair and all my own teeth! As far as I know I have no extra legs, arms or a large flashing banner above my head. But I still spend a large part of my working life listening to people say things like: "Oh, you're not what I expected!" Why? I'm head of science in an inner-city comprehensive and have been for more than a year. To make matters even more eyebrow-raising, I joined the school in 2002 as an NQT (you do the maths).
This wasn't in my career development plan at university, but here I am having endless conversations with visitors to the school, advisers, sales people and colleagues telling me I'm strange, mad or plain stupid. I can accept the mad (I suspect it's a job requirement), but the rest is offensive. My school has been fantastically supportive, but I've been on courses where people have refused to talk to me once they find out what I do, spoken to advisers who won't listen because they think I don't know what I'm talking about, been told that eventually "I'll learn", and heard heads of other departments say standards are dropping.
I don't know all there is to know about teaching, but I've seen enough to know that few teachers do, and I'm self-aware enough to know that the learning cliff (curve doesn't quite describe it) I faced and successfully navigated taught me things I will never forget.
The last year has passed in a whirlwind of supply teachers, NQTs, sick technicians, tears (the NQTs) and tantrums (mine). I've rearranged key stage 3, brought in a new course, organised exams, spent budgets, allocated timetables, moderated coursework, achieved the same exam results as the year before, disciplined pupils, supported supply and trained new staff, only then to be told I'm not old enough.
It is this attitude that makes me worry for teaching in general, and science teaching specifically. We have enough trouble in my school getting pupils to accept a female science teacher without the added cynicism of other teachers. I worked hard for my three A-levels in science and know as much as any older person about the science curriculum.
The leadership and teaching part comes with experience, but it has to be your own; you can't teach someone to run a department effectively until they are doing it themselves. As the older generation in the profession retires it is going to fall to the young to pick up these management places. Surely it would make more sense to offer encouragement rather than pat people in my position on the head and tell us to come back when our hair is grey because only then we will have earned our stripes.
Sarah Murcott is head of science at Castle Vale school, Birmingham