Since opening the Idler Academy almost a year ago, one of our preoccupations has been English grammar. We have programmed a couple of lessons on the subject and published our own grammar guide because we have spotted that it is simply not taught in schools, with the result that young people go into the world with a very poor command of their own language.

This may have sounded like an eccentric position to some. But it seems we are on to something, because in one of the most unexpected developments of the past year, the Idler Academy has been enfolded in the warm embrace of retail giant Selfridges, which has let us into its basement to give lessons in some of our favourite subjects. This suggests that far from being a fusty and eccentric subject, grammar is, in fact, hot right now.

The Oxford Street department store came to visit the Academy in October and invited us to programme a series of talks and classes as part of its "Words Words Words" season. Accordingly we have organised lessons in Latin, book-making, embroidery, grammar and calligraphy, and these events take place, for free, in a new library in the Selfridges basement built for the purpose.

Selfridges was particularly keen on the grammar lessons offered by Mr Gwynne, a septuagenarian old Etonian and retired businessman, and booked him in forsix. So it was that last Friday Victoria and I witnessed the bizarre spectacle of a suited Mr Gwynne giving a lecture to Oxford Street shoppers on the parts of speech and correct use of the apostrophe. He had the assembled audience reciting in rote fashion: "A pronoun is a word that stands in place of a noun." Mr Gwynne also accused Selfridges itself of poor grammar by dropping the apostrophe it featured in former times, and he also informed us that Waterstone's was planning to rebrand itself Waterstones. Surely, he said, it is unseemly for a bookseller to make such a fundamental error. The audience joined the conversation enthusiastically and moved on to debate the role of the semi-colon.

There is more evidence of grammar fever. Selfridges is now stocking our booklet "Gwynne's Grammar", written by Mr Gwynne and published by The Idler. To its surprise, the grammars sold out in two days. The store also found that a selection of second-hand books which we had supplied sold briskly, and I am now packing a new order which includes a Latin dictionary and Greek lexicon.

Why does Selfridges want to educate its customers? Well, Selfridges can do this sort of thing partly because it is a private company. It is not listed on the stock exchange, and this means it has more freedom than corporations, which by their very nature prioritise the bottom line. Its other distinguishing feature is its creative director, Alannah Weston. She is the groovy fortysomething daughter of the owner, the Canadian businessman Galen Weston, and she is the force behind these creative projects. Modern shoppers, she says, "want intellectual, cultural and, yes, spiritual nourishment. They don't just want to buy things."

Noble sentiments, you might say, from a shopkeeper. And cynics might argue that for Selfridges, such projects are merely a trick to get punters through the door. But I think there is a genuine desire to offer people good-quality information and teaching. It seems that Selfridges and people generally are in agreement with our conviction that it is a crying shame that grammar, Latin, calligraphy and Greek philosophy are no longer taught in schools, and there is a real thirst out there for such knowledge. What we see in our lessons is a joy in the process of learning, thinking and talking. This kind of intellectual engagement brings an almost physical pleasure and satisfaction that is beyond sex, drugs and rock'n'roll. It does seem to be true, as Aristotle said, that real happiness is found in contemplation, study and debate. And like the Stoics, why not teach our lessons in the marketplace? Let us go out to the shoppers.

There is also something very gratifying in the fact that the Selfridges lessons are free. In a peculiar development the retail giant has joined in the spirit of free education embodied by temporary institutions such as the Occupy movement's free universities. Funnily enough an anarchist friend in the US, who you might expect to disapprove of The Idler entering a temple of consumerism, wrote me a congratulatory email which said he wished American retailers would provide a space for words.

It seems that purely by chance The Idler has found itself at the cutting edge of retail.

Tom Hodgkinson is editor of 'The Idler'