George is finally leaving. “How will the school manage without its longest serving stalwart?” asks the head at morning briefing, before wandering over for a quiet word. It seems that you might be able to help with the answer to this question.

Every school has a George, or a Georgina. They run the sports teams, organise the parent-teacher association, take kids on trips, sort out the staffroom tea roster, do the displays in the entrance hall - in short, they make the place hum.

But how do these jobs get allocated? Did George volunteer, or did his workload just grow over the years? Was he a deputy, paid a stonking great salary for doing all this work, or was being the cornerstone of the school written into his contract when he wasn’t looking?

Every teacher needs to think about the Georges of the world because if you teach in a school for long enough some of these jobs will be steered in your direction. It can happen at interview. Just after you have been offered the job, when you are feeling full of yourself; the head will ask whether you might be willing to take on X or Y.

Or it may be an ad hoc approach; slipped into a corridor chat, or added to any other business at the end of a boring meeting. “How do you feel about taking on... ?” says the voice of management.

Sometimes you will have been covering for someone else. Jane couldn’t drive the minibus this week and the Year 6s were going to miss their match. Yes, of course you would fill in. But it turns out that Jane’s indisposition is permanent. The kids are asking you whether you can take them next week.

You’ve just acquired another job.

The fact that the kids love their match days, and that you quite enjoyed taking them and watching them play is not the point. The questions should be: Is this something you really want to do? Do you have time to do it? What will you gain if you take this on?

To some people this will have echoes of I’m Alright Jack, the 1959 Ealing comedy in which Peter Sellers famously parodied the archetypal union official. The film lampooned the lunacy of the demarcation dispute and the culture of rule books, bonuses, tea breaks and workers’ rights.

Most teachers who run voluntary activities in schools do so because they want to; there’s no compulsion. But there’s a hazy dividing line between volunteering and being press-ganged.

And in many cases the job is a real job, not an extra-curricular activity.

Exams officer, duty team leader, head of year, primary liaison; these are management roles and no one should be asked to do this kind of job on a casual basis.

In one school, a head of department decided that it would be good for the team if they all had some experience of exam marking. Teachers found themselves spending the first week of their summer holiday marking GCSE scripts.

Another teacher was offered a management allowance to become head of careers. This, she thought, involved liaising with the careers service and keeping the school’s careers library up to date. Then came Connexions and the focus on “difficult” children, and she found herself running work experience, organising careers interviews and being sent on careers courses. Yet her job description never changed, and neither did her salary.

In primary schools, teachers are often asked to take on responsibility for a curriculum area without any financial recognition of the extra work and responsibility. In one case, a newly qualified teacher in her induction year was asked to take on the special educational needs co-ordinator role, responsible for all the school’s special needs children at a time when she should have been focusing on her own professional development.

New rules on promoted posts introduced this year will complicate the way that these jobs are allocated. In future, management points will only be awarded for posts that directly involve teaching and learning.

Administrative jobs - such as examination officer - fall outside this definition and will have to be done by support staff.

But there’s a loophole. Who will manage the support staff? Many schools are moving to a flat management structure, where a head directs a team of “leaders”, who in turn direct the teaching and support staff. This kind of distributed leadership is the model promoted by the National College for School Leadership. It opens up the possibility of a promoted post, ostensibly focused on managing a department or key stage, but which also involves management responsibility for teaching assistants, or cross phase liaison or work experience.

At least these managers will be paid to take the responsibility. The main problem in schools is the job that comes with no reward attached. Schools can take the uncertainly out of these issues by offering all their teachers clear job descriptions, with a regular review to see whether the paper description actually matches the job being done.

But teachers also need to learn the art of saying no. And heads and teachers together need to explore the various ways that the school could offer some kind of recompense for the work done. Creative heads may be able to offer a PE or drama teacher a separate contract for the out of hours work they do. It may not pay a fortune, but it’s recognition of the work.

Or there’s time. Heads and governing bodies could compensate teachers for the extra work by giving them extra free periods, or a day off covered by a supply teacher.

Some schools offer their school trip leaders time out for visits to possible venues and planning time for the paperwork that all trips generate.

It’s a quid pro quo. You scratch my back, I’ll scratch yours. But some heads will blanch at the idea. They will plead poverty, and some of them will be right to do so. But if the head who sidles up to you in the staffroom has just bought a new IT suite, or spent 20 grand on a new entrance hall, then I’d suggest that the request that you might consider picking up where George left off merits a very simple reply.

Two words should do it:

“No thanks.”