Tom looks at me resentfully. "Sorry, Jonny," he says. My anger dissipates. I'm holding his mechanics assignment, handed in late, one of three he owes me. It is a swiftly-executed copy of the specimen answers, presumably borrowed from someone else. A few numbers and expressions have been altered to give the impression of authenticity, but I have not been fooled.
"What about Cambridge, Tom?" I ask. Tom is (usually) one of the brightest students I have ever taught. He wants to go to Cambridge and he ticks all of my boxes for this: lightning assimilation of concepts and techniques, with a creative mind and a healthy self-confidence. The only question mark is a certain wildness of temperament, leading to unreliability.
"Oh, I'll get to Cambridge," he says. "I'll work at the end, like I did last year." Tom's mercurial approach caused a scare at AS, but he shut himself away to revise for a solid fortnight, with spectacular results. He has an offer from Cambridge that is achievable. But in his A2 year, girlfriends have taken over.
"A2 is different from AS, Tom," I explain. "It's much harder to be last minute. You can't resit the exams ahead. This is February. If you dedicate yourself to study until July, you can do it."
Tom works in a local bar. "How many hours' paid work are you doing?" I ask gently. "Twenty-five a week? Can't you see how crazy that is, Tom? What would going to Cambridge do for your earning power over a career? You do the math."
"I need the money," he says stubbornly.
"For your social life?" I ask. "Can't you put that on ice temporarily? Unless - you need the money for other reasons?"
Tom's eyes say, "Don't go there." Some students support their families. I change tack.
"I can't stand over you with a big stick, nor can your parents," I say. "Even if we did, who would do that for you at Cambridge? Or in your first job? It has to come from you, Tom."
"I just don't like being told what to do," he says. "Are we done?"
I look at this boy-man with sadness and say: "Tom, I'm asking you to do yourself justice. But it's your life. I understand that."
Tom gives me one last stare before walking out. He is fictional but this conversation sadly represents many such encounters.
Jonny Griffiths teaches maths at a sixth-form college
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