"When Jacob was offered a place, I cried. He was shocked. But my husband wasn't"

We thought we'd put it all behind us. Two years ago, Jacob, our eldest, secured himself a place in our first-choice secondary school and so our two younger children were effectively assured of a place as siblings. We relaxed – job done, roll on Oxbridge entrance. But then a month ago we woke up to the fact that our middle-born was a girl. What about all those girls-only schools? It would be irresponsible, surely, not to check them out?

So we took her off to an open day, but with only a modicum of enthusiasm. And, yes, she, and we, fell in love with one of the most impressive girls' schools in south London. Our hopes for an anxiety-free Christmas were dashed.

It's a strange sort of anxiety – unique, appalling, and frustrating. The worst part is the powerlessness: yes, you can train them for the tests but there's little else in your control. The very reason the schools have become sought-after is that they operate some sort of selection process, whether it's a test, an interview or, in the case of some church schools, a close analysis of your religious fervour.

We've been turned down before. In 1994, when Jacob failed to get a place at the primary of our choice, we knew there was no point in appealing. The rules had been applied fair and square. Fortunately, our despair was short-lived. After a couple of terms at another local school, our evangelical belief in The Waiting List paid off.

Maybe it was the chill memory of this experience that made us start looking at secondary schools when he was still in Year Five. We wanted to know exactly what was out there, and, being zealously committed to the state system, we wanted to have our answers ready for all the private-sector backsliders.

After a couple of depressing open days, we found in Putney a magnificent comprehensive which took in all abilities and yet created a harmonious, hard-working environment. And in Tooting, we found a semi-selective comprehensive which looked just like a grammar school of old and had the same reassuring aura of academic rigour.

And so we started practising for the tests – a full year in advance. Was it a bind? Yes and no. Yes, any extra work on top of spellings, equations and the project about the Pharaohs is bloody boring. And you don't know the true meaning of boredom until you've slogged through a Non-Verbal Reasoning test. ("In the boxes on the left are shapes and the code letters that go with them. The top letters mean something different to the bottom ones. You must decide how the letters go with the shapes then find the correct code ... ")

But there's an up-side. These tests guaranteed that Jacob would – if he succeeded – find himself among his peers. If your child is bright, you have a duty to find him a school where he is allowed to be exactly that – where he can flourish, where he can luxuriate in his own desire to learn. And these tests ensure this. Just as much as the low-achievers need special help, so too the higher-achievers need the chance to stretch themselves.

Better still, practising for the tests reduced our sense of powerlessness. Poor kid, you're thinking. But don't worry, he loved it. He could win £1, £2 or £5 (according to his marks) for a mere 50 minutes' concentration. He used to beg us for another test.

Then, just when we were confident, the Schools Adjudicator stepped in: where previously the school had been allowed to take half its intake from the selection test, this was slashed to 25 per cent. Only half the number of places, 67 in all. Now we're talking sweat: we upped the practice, we bought more practice papers, we took out a second mortgage to cover Jacob's bribes. And then, the day before the test, the High Court over-ruled the Schools Adjudicator: back to 125 places from the test. For this relief, much thanks – but too late, too late to mitigate parental stress.

When the letter came offering Jacob a place, I burst into tears. The kids were rather surprised, but their father wasn't. There can be no greater security than knowing your child will spend those vital years in the environment of your choice.

Next Saturday Chloë takes her first test. We've been back to the Verbal (manageable) and Non-Verbal Reasoning (impossible) and Maths (Daddy only). We are very tired. So, anyone out there expecting their first baby, here's my advice. Forget the antenatal classes. All that breathing is only useful for a few hours; education is for ever. Bin the yoga books, hit WH Smith's, get yourself a test sheet, and start practising.