The question of extra payments to headteachers and, indeed, to anyone on the leadership spine, is a vexed one. The key point is that, while all teachers not on the leadership spine are limited, by their conditions of service, to 1,265 hours’ work per year, there is no such limitation on the hours worked by heads, deputies and assistant heads.

Thus, while it is possible for a teacher to take an additional contract, which does not interfere with work within the 1,265 hours, this option is not open to senior managers, because there is no limit and it is therefore impossible to determine what is outside it.

This obvious injustice applies not just to lunchtime supervision but to after-school activities, summer schools, Easter revision sessions and any other commitments outside normal hours for which additional remuneration is available.

It might be argued, in respect of lunchtime, that a head is responsible for the general supervision of the school at that time and that this is, indeed, an integral part of his or her duties. The same argument does not necessarily apply to other activities.

Last term we used a supply teacher provided for us by an agency. When we advertised the vacant permanent post, this teacher applied and was appointed. The agency is now demanding a fee from us. Must we pay?

I do not know, because I have not seen the agreement that you signed or otherwise accepted with the agency.

This may well be a cautionary tale about the desirability of always reading the small print. If there is indeed a clause which states that, in the event of a supply teacher provided by the agency being appointed to a permanent post, a specified fee is payable, you will have little option but to pay up gracefully. If there is not, then you should challenge the agency’s demand.