Despite the whiff of sexism, Shakespeare had a point.
"One man in his time plays many parts." I never dreamed, though, that retirement would entail learning the part of a teacher.
Every profession involves a bit of teaching.
For a year, I taught a course on the 1916 Easter Rebellion in the attic of the Theology building at Queen's University in Canada.
After that initial sparring I gave lectures, speeches and tutorials, but never once imagined that my home would be transformed into a high-tech version of the School of the Air.
In lockdown, we now home school our three grandsons, following a curriculum set by their normal school eight hours' flight away.
Written instructions from school are supplemented by Zoom calls (garbled), teacher videos (encouraging), slide packs (daunting), exercises (interminable) and daily feedback (sometimes chastening).
Their service is exemplary: the weak link is me.
Relief seeps in when I can - just - manage those calculations about train routes, odd socks, pizza slices and vulgar fractions which enliven primary school maths.
English is easier, though it hurts to correct a seven- year-old's credible, phonetic spellings of "ubuv", "gardien" and "pepol".
Why do we not spell those words that way?
Wellbeing assignments I let go through to the keeper, apart from one taxing bout with the banana banana meatball dance.
The problem is not the curriculum but the stand-in teacher.
Students through the generations have mucked about and played up whenever a substitute teacher turns up.
They often inspire no love, provoke no fear, impose no discipline.
I, however, had never seen strict rules and performance indicators as part of my remit as a grandparent.
When anyone complains that we spoil our grandsons, we claim that verb is out-of-date and should be replaced by "look after".
If invited to assist with homework, I used to respond that my essential job was to help turn the kids into addicted readers.
With that benign addiction, all good things would flow.
Detailed discussions with my oldest grandson have now shifted from fantasy football to virus tracking statistics, from Hot Wheels toy cars to the engine capacity of a Porsche 911 GT 2RS.
The ignorance on my side remains compendious, but the youngster cuts me some slack.
As for bad behaviour, we know how to cope with the "hungry naughties", an odd tantrum and bouts of sibling rivalry.
You can find those foibles at work as well.
Now we have to choreograph three grandsons "creeping like snail unwillingly to school".
I asked the oldest for advice on how to persuade the two younger boys actually to do some work.
"Bribe them", he declared, "then make everything a competition".
That was a wise answer, worthy of credit in a wellbeing course.
One additional lure was taken for granted; extra screen time is the modern equivalent of glass beads, pocket money and other traditional items of barter trade.
Nonetheless, even heeding the advice, we worry about erosion of our standing as grandparents.
Instead of being reliably warm, kind, soft and happy, we fret about turning into firm bossy-boots.
We want unqualified, unalloyed love back again, not affection muffled by maths equations or muddled up with spelling mistakes.
Before and after lessons, we can revert to our preferred roles.
We can spend time kicking a footy or throwing a frisbee, putting on a DVD matinee or making biscuits together.
The grandsons can laugh and lollop as well as learning.
This is not remembrance of things past, but a forecast of better times to come, after we happily drop them back to school each day.