My friend Katie tells me not to start sentences with ?in my day?. She says it?s time for a linguistic botox. As soon as she says this, every remark I make begins ?in my day?. In my day, parents didn?t spend so much time parenting. Because in my day, children weren?t the center of the universe, we were just co-residents in the family house. Parents had what Bill Bryson calls ?amicable dementia??they never quite knew what you did after school, if you did your homework, if you succumbed to peer pressure. We weren?t the center of their universe, the sun to their moon. We were just minor planets with names, and as long as nothing appeared on our report card that brought shame on the family??if she misses gym class one more time, she will be expelled??life went on.

In my day, parents weren?t philosophical. They didn?t give us advice for a fulfilling life. They said: ?If you don?t pass algebra, you won?t go anywhere for six weeks?. They never said: ?All through your life, you will have to do things that seem irrelevant. Learn to do them quickly and well, and then you can shove them out of sight?. They didn?t say things like Nick Carraway?s father in The Great Gatsby: ?Whenever you feel like criticising any one? just remember that all the people in this world haven?t had the advantages you?ve had?. Which doesn?t sound as profound now as it did in my day.

But times have changed and never am I more aware of it than in these days before taking Sam back to school. The biggest sign of change is feet. Despite the fact that all the serious newspapers have turned into magazines, with as many articles on ?the 10 best hairdryers? as on global warming, no one has written about the dramatic growth in boys? foot sizes. Even the shoe industry hasn?t kept up. Men?s shoes stop at size 12. My son, aged 17, wears a size 13, as do five of his friends. And you know what they say about men with big feet. Big socks. British sock sizes are size EU 41?45, equivalent to shoe size 7?11. Only at TK Maxx can we buy ?Big Foot Socks?, for feet size 12?14. I buy in bulk.

If only I could stick to shopping, these days leading up to Sam?s return to school would be idyllic. But I feel the need for meaningful heart-to-hearts while I have his undivided attention?that is to say, while he is eating a dozen oysters at Loch Fyne, one of many ritual lunches leading up to his Last Day. I tell him that in my day there were no farewell meals in restaurants. ?There were restaurants in your day?? he asks, solemnly sipping his Muscadet sur lies.

I plough on. I tell him the story of Martin Luther King Jr mopping the kitchen floor. Large patches hadn?t even been grazed by the mop. ?Do it right,? his mother told him. ?Mop that floor as though your life depended on it.? I begin to explain how mopping the floor as though your life depends on it leads to greatness. Sam looks up from his oysters. ?Ma, you tell me that story every year.?

I try to lighten up. ?Okay,? I say, ?never skip breakfast: it kick-starts your metabolism. Don?t waste time learning the tricks of the trade: learn the trade. Keep your watch five minutes fast. Be kind to the new boys.Call home or I?ll report your phone lost.?

This is Sam?s last year at school. My days for telling him how to live a happy life are numbered. Finally, I tell him just to remember the words of the immortal B. B. King: nobody loves you like your mama. And even she might be jivin?.