I see a lot of stress. Undergraduates who have crammed into the small hours and arrive looking gaunt, pale and anxious. Some simply can't cope and we have to let them out before their distress has an impact on others; some wander in looking confident, only to be visibly shaken when they turn over the exam paper and the reality of their lack of preparation becomes all too apparent.

I've seen it all: youngsters walking out, throwing up, even breaking into giggles. This is the sharp end of the educational treadmill: three years of study distilled into a few hours of pure pressure. And, of course, you get cheating. The first thing to look for is simply body language – you'd be amazed at how easy it is to spot furtive behaviour. It's sad, but reporting this sort of thing goes with the territory. After all, it's the other students who've put in the effort who suffer.

At the end of the exam, I notice the aftershock kick in. A few break the tension by exploding with relief, and most can't wait to get out of the torture chamber, but some just stare emptily into the distance and have to be almost prised out of their chairs.

I never see the full results of their efforts, but I do wonder. Sometimes, as I patrol the room, I look down and witness a disaster in the making, with lots of crossings-out and moments of panic as a candidate realises they've made a huge cock-up.

So am I a fan of exams as a method of assessment? Yes, sure. Without them, I wouldn't have a job.

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