Briefcases were not designed for teaching. It was different in the old days, when capacious leather holdalls disguised as briefcases were sold in dimly lit leather emporia complete with a lifetime guarantee. Your lifetime that is.
Today's slimline, imitation leather executive accessory is half full after three sheets of A4, and as for 3B's maths homework - forget it. The trouble is that the ideal receptacle for a teachers essential kit hasn't yet been invented. Just think what it would have to contain.
There are the classroom emergency supplies. Pens, paper, pencils, gluestick and scissors. Tissues to deal with Nigel's nose - few teachers can work efficiently with a runny nose on the front row.
All these could of course be left in your desk drawer, along with essential files like the Office for Standards in Education handbook and the draft school policy on the use of drawing pins - ensure that the thumb engages with the circular flat section and that the sharp, pointed part of the device is firmly pressed against the display surface.
But experience suggests that really useful resources, like sugar paper and unchewed rulers, have a tendency to go walkabout.
Sometimes this is down to small fingers, but often it is colleagues, who soon discover which rooms have a rich supply of goodies and are won't to nip in and borrow things while you are busy with Nigel's nose.
And then there are the other essentials of a teaching day, like Hobnobs and paracetamol. The ideal receptacle would have room for a lunchbox and, instead of a pouch for a mobile phone, there would space for a capacious flask.
In the absence of a properly designed teacher's kitbag people improvise: rucksacks suitable for a Himalayan expedition, Tesco bags, a variety of sports bags. One newly qualified teacher found a Head bag ideal until he was severely reprimanded by a deputy for carrying it slung over his shoulders a la Year 10.
Airline cabin bags have lots of useful pockets and, at a pinch, can be used to illustrate the geography of the Mediterranean when you have to cover a lesson at short notice.
There are also those teachers who prefer the multiples option. Rather like Zsa Zsa Gabor, who never travels anywhere without 58 items of hand stitched luggage.
These teachers carry everything everywhere and can often be seen struggling back into school with handbag, holdall and three Tesco bags full of marking - none of which got done because they were showing repeats of Pride and Prejudice on BBC2.
Perhaps the best solution is to carry as little as possible. A recent correspondent on The TES letters page chided colleagues for their inability to manage their school day without taking hours of work home.
The answer, the writer felt, lay in proper preparation and time management.
A modern, cardboard framed briefcase would therefore be ideal. Buy one of those and it will be impossible to take more than a few reports home.
And Nigel should supply his own tissues.