Joanna Briscoe: This is the life

Diane Abbott's decision to send her kid to a hothouse for posh gits rather than her local Hackney academy of glue-sniffing marks her out as a hypocrite. Just like the rest of us, then. I'm all for abandoning your socialist principles if you've got a febrile young swot on your hands who'd be better off hoovering up Ancient Greek in a cloister than gouging out compass tattoos during Media Studies. But there is something to be said for

slumming it in a sink school. As long as the establishment in question is a truly catastrophic little dump, and as long as you don't get killed while you're there, it may well inspire flights of rebellious, despairing creativity that a violins-and-boaters haven would slaughter with an S-level.

I for one was taught in a cow shed.

I never quite got over the shock of arriving at my education-free rural comprehensive after spending two years at a gels' grammar with quads and choral societies and tufty-haired mistresses who lived with their dogs or each other. My family had re-located to the sticks and while my siblings misbehaved expensively at the private school up the road, I, being the least demanding, was parked at the compost heap, to employ local terminology. There I wrinkled up my retroussé snob's nose at this heaving stadium of bullet-headed boys and big-bosomed giants with feathercuts and flares whose Bics had never tangled with an apostrophe.

The trauma of an educationally subnormal school instantly turned me into a raving swot. My school days were spent rolling around in mud as I clung to my fountain pen, crying out for Latin lessons. I befriended the school's resident triumvirate of howling snobs and we spent our days polishing our A-grades and hooting in a corner about everyone else.

As if proof were needed, Cowpat Comp had a farm in the middle of its grounds. I imagined it to be some Marie-Antoinette-style folly, the quaint yet smelly alternative to a perfectly good quadrangle. It was only years later that I questioned a friend about its existence. "It was for all those people who were too thick to wield a pencil," she said in matter-of-fact tones. "Didn't you realise?" No I did not.

Eventually, I learned to stay at home. Not to play truant, but because I had calculated the cramming time I lost by driving down 15 miles of mud track behind cows' bottoms only to be instructed for a few hours between General Studies and a fight. At home, I could fit in six hours of revision before a strenuous lucubration session and a nightly attempt to become a child prodigy of a novelist, instead of idling at an establishment that favoured mucking-out lessons over matins. Said school commented mildly on my absences, but clearly my autodidact's ways produced results.

That was then. It's now de rigueur for the middle classes to wriggle their way into a decent school: rules miraculously melt, politics develop schizophrenia and an urgent desire to cheat the system sets in. But in a perverse way, by cheating you cheat your child of something else. In my experience, ingenuity and artistic impulses can flourish in adversity.

I was sufficiently piqued, indignant, and somehow creatively inspired by that lack of pedantry to want to plot my way out. OK, you're more likely to get your head kicked in, develop nervous eczema and grievously underachieve at your average gutter comp than to emerge triumphant, but it can serve its purposes by fostering the determination to escape and prove the bastards wrong. And wherever you are, from deepest Hackney to dung-splattered nowhere, there's always one: one Jean Brodie, one shining beacon of academic inspiration in the wilderness. Thank you, that English teacher of mine who was a true glory; who understood grammar, of all things, and towered, suitably god-like above the rest of them.

The majority of my well-educated grammar school peers emerged from the quads as good-girl librarians and solicitors. In contrast, my compost heap contemporaries included the writer Toby Young and the newscaster Mary Nightingale, while the novelist Penny Vincenzi attended the school when it was still a grammar.

And anyway, after all that, I loved it! In the face of howling academic frustration, it was the making of me. It was raging fun. It was The Archers incarnate, one wild and woolly, cackling great soap opera whose idiosyncrasies inspired me for ever. When the privately educated are constantly prattling on about their scholarships, exeats, Latin orations and lacrosse, I take great pride in announcing I'm an alumna of Cowpat Comp. My area of excellence: milking classes. It's very useful for a life as an urban-dwelling writer.