Our grandchildren are penniless. They have pretty much everything their hearts desire and they have parents with wallets full of plastic, but they lack the satisfying chink of coins in a jam jar.

I was alerted to this state of affairs when one of our tribe turned nine and I asked his mother how much pocket money he was getting. The answer was: nothing. The very words ‘pocket money’ seemed to strike her as quaint.

I said: ‘But what if he wants to walk down to the shops to buy a comic?’ The answer was that such a thing was very unlikely to occur to him but, if it did, she would drive him to the shop and pay for the comic.

There, in a nutshell, were two worrying trends. If his mother always pays for everything, what possible chance does he have to understand money? And if he never walks to the corner shop without a hovering adult, when is he going to learn to deal with traffic, cruising pervs and big boys intent on robbing him?

My interest was piqued. I cast my net wider. A granddaughter, also aged nine, informed me that money comes from a machine. You just press the keypad and money comes out. And what if it doesn’t? What if it says ‘insufficient funds’? Well duh, you just go to another machine. She had no idea there was a connection between her parents enduring the Victoria Line rush-hour twice a day and the cash dispensed by the Money Fairy from a hole in the wall.

Speaking of fairies, the Tooth Fairy does still visit, giving today’s child a rare encounter with coin of the realm. I’m told the going rate for a cavity-free milk tooth is a quid, but trending strongly towards £2.

Times change, of course. I’m not hankering for a return to the days when Dad came home on Friday night, put a wage packet on the table and then watched while Mother divvied it out, so much for the milkman, so much for the rent, and a pile of coins for the Man from the Pru, because he liked the exact money. However, I do think our grandchildren might benefit from exposure to some archaic financial practices. Saving up for something, for instance.

I was staying with another twig of the family tree and a granddaughter was canvassing for a particular doll, a must-have in the school playground among Year Five girls. It wasn’t expensive and she’s not a greedy child. I could see that her parents were likely to buy the damned doll before the weekend was over. But as I had also noticed that she left making her bed to some unseen servant, I thought it was an opportunity too good to miss.

I drew up a chart, fixed a tariff and, when my visit came to an end, left a cash float with her parents. Ten pence per bed made, but no reminding, nagging or sub–contracting allowed.

I count the experiment a double success because by the end of the first week she had acquired the good habit of making her bed every morning and by the end of week ten  she had enough money to buy the doll. Which she no longer desired quite so much. Perhaps that counts as a third lesson learned: the wisdom of a purchase deferred.

Of course, children do still see cash. Bubble gum machines take coins. So do school fêtes and roadside fruit sellers. But for how much longer in a world where there is now a cashless, digital version of Monopoly? No wads of paper money to wave in the face of your opponents, no reason to channel your inner Rachman or arm-wrestle for your turn as Chairman of the Bank of Evil. Finagling and short-changing have been rendered impossible, boo hiss, and Mr Monopoly has been reduced to a voice-activated accountant. If this abomination turns up in any household related to me, I shall refuse to play. I’ll cleave to the old-fashioned Cheater’s Edition.

The writing really is on the wall, though. Buskers who take cards, public inconveniences where you can no longer spend a penny. Even the Church of England started going contactless a couple of years ago. Not the Welsh Church of Central London, though, which I visited the last time I was in London and where, to my great embarrassment, I found all I had in my purse was a fistful of brown coins. Agreed, on that occasion a digital collection plate would have saved my blushes.

The cashless childhood seems all but accomplished. Will the next generation know the joy of having Grandad conjure a shiny coin from behind their ears? And then the thrill of spending it?