Nobody likes covering for absent colleagues but, unlike teachers in France and many other countries, everybody has to do it. It can be particularly difficult for new teachers, even where schools have a policy of protecting them from it as much as possible.
There are three main problems with cover: first you can never be sure when you'll be asked to do it; second, the absent teacher may not have left adequate - or sometimes, even, any - work; and third, the young people hate it. Whatever they feel about their regular teacher they'd almost always rather have him or her than a substitute.
It's a situation which draws on all a teacher's ingenuity, management skills and understanding. It can so easily become a disaster.
What can be done to ensure an unsatisfactory situation is made as tolerable as possible and, what is even more important, that students learn without their usual teacher?
Part of the answer lies in the school's policies. Where cover lessons are taken seriously and there is a genuine commitment to making them as good as possible, any teacher who knows they are going to be absent will ensure the replacement has plenty of work which follows what the class has done previously, and that the briefing notes are detailed and cover every imaginable eventuality. The students will probably have been briefed as well. He or she will also make sure that materials are available along with the keys to cupboards which contain anything else that might be needed.
Somebody who is unexpectedly away, because of illness or some unforeseeable circumstance will, when alerting school to their absence, give detailed notes, indicate where everything can be found and draw the cover teacher's attention to any particular issues. The head of department or somebody else in the team is also likely to be there at the beginning of the lesson to smooth the way.
Unfortunately, this is not always the scenario and the resourceful teacher must be prepared to walk into a chaotic situation where nobody is clear what the students should be doing, all the equipment is locked away and the pupils "can't remember" what they did last lesson.
Whatever happens, stay calm! As all supply teachers know, the worst thing is to panic or give any indication that you are not in complete control of the situation. By a little judicious questioning of students and some investigation - particularly if the absent teacher uses a planner and leaves it at school - you may find that the situation is not as bad as it first appears. If it is, then Plan B comes into operation.
Plan B is in two parts: either the department will have standby activities - usually worksheets or lesson plans for all eventualities - or the cover teacher must provide them. If you're in a school where this kind of thing happens, you would be well advised to spend time devising some interesting lessons for unexpected occasions, as well as working to change the culture of cover work.
These should not be simply time fillers: they must contain learning and challenge or the students will take out their frustration on you rather than the absent teacher who has left them unprovided for. And they'll be doubly fed up if they've been provided with inadequate fare from a cover teacher in a previous lesson. It doesn't matter that the work is not in the subject you're covering for, as long as it's worthwhile.
Cover lessons can be a good test of your relations with children, particularly if the class includes people you teach in your own subject. In somebody else's classroom they may behave quite differently but they'll expect you to be the same. If you are normally energetic and interested, that's what they'll expect from you. They'll be very unhappy if, like some teachers, you use a cover lesson to finish your marking or do some other routine task.
And why shouldn't they feel miffed in those circumstances? If you went to a theatre and found an understudy simply going through the motions in the absence of the star you'd feel entitled to ask for your money back. That's how young people feel when a cover teacher doesn't give them the attention they're used to.
It's important, too, at the end of a cover lesson to report in some way to the regular teacher. Some schools have official feedback forms but a note relating the work covered and any problems will work just as well.
If that feels like a chore, just remember that you're going to be absent yourself some day and you'll be glad of the information when you return.
That is the most significant factor about cover: everybody does it and everybody, at some time, is away from school, therefore everybody has a vested interest in making it work as well as possible. If your school is a shambles when it comes to cover, perhaps it's time the truth was pointed out.
Mike Fielding was formerly principal of The Community College, Chulmleigh, north Devon