You are not a specialist physics teacher, but you feel reasonably confident about this part of the scheme of work. There is a productive buzz around the room as the pupils work in pairs, drawing in the force arrows.
One of the girls, Anita, puts her hand up. "Miss," she says, "I know that gravity pulls down on the computer, but how can the table push upwards? - the computer's just sitting there. The table can't be pushing up - it's not alive!"
You pause for a moment, thinking: "Yes, it's true the computer is just sitting there. Have I got this right? Is the table pushing up?"
A number of pairs of eyes are now looking your way. Yes, the table must be pushing up, or else the forces wouldn't balance. But how to explain it to the class?
This kind of scenario must occur every day in schools across the country as science teachers find themselves working with pupils in curriculum areas that lie outside their specialism. It might be the chemistry teacher teaching biology, or the physics teacher teaching chemistry. But given the drastic shortage of physics teachers at the moment, it's most likely that chemistry and biology teachers will be taking on the physics role, particularly at key stage 3.
The challenge of effective physics teaching is summed up in the example of Anita. In order to give a satisfactory response, the teacher must be able to understand the pupil's problem and the solution in terms of physics, as well as provide an explanation that makes the notion of a table pushing upwards plausible to pupils.
The experienced physics teacher will respond with a knowing smile, having heard the question a number of times before, and might answer: "That's a good question, Anita - the idea of the table pushing up is difficult to believe, but think about it like thisI" The Institute of Physics is engaged in a new initiative which aims to support non-specialists in teaching physics at key stage 3 and strengthen teachers' confidence in teaching physics. Called "Supporting Physics Teaching (SPT) 11-14", the scheme is based on CD-ROMs which teachers can work through in custom-designed professional development programmes.
The CD-ROMs bring together the three key components which the Institute believes are essential in physics teaching:a clear account of the subject matter; the areas that pupils find difficult; and the teaching approaches, including activities and explanations.
These resources are being developed through a network of university lecturers in physics education who are working with teams of physics, chemistry and biology teachers. The first professional development programmes, using a pilot CD-ROM, will take place this summer. Asuite of materials addressing the whole of key stage 3 physics is due to be available by the end of 2004.
And what did the teacher reply to Anita? Sorry, to find out you'll have to look it up in the SPT package.
Dr Phil Scott is senior lecturer in physics education at the University of Leeds.
For more details on the scheme contact Ingrid Walker (project administrator) at the Institute of Physics, 76 Portland Place, London W1B 1NT; email: firstname.lastname@example.org