Never go back! Isn't that what they say? The trouble is, some of us don't listen.
I went back to my old primary school after 20 years. It had been demolished. After 25 years I went back to my old secondary school. But it had been turned into, of all things, a college. This time I went back to the college where I trained as an FE lecturer after 30 years - and my old teacher was still there.
Admittedly, he was the only one. And he has gone up in the world since 1976. Now he's running the place: Edwin Webb, the head of department for post-compulsory education and training, no less.
Ed (we called him that in my day) is not alone in the elevation stakes either. The college itself has become a much classier joint since 1976.
Then - as Garnett College - it was housed in a decidedly ordinary 1960s building on the edge of a council estate in south-west London.
Now it's part of the University of Greenwich, and classes proceed amid the palatial splendour of the Old Royal Naval College by Thames, with views across the river to the Millennium Dome.
Happily, the course has changed too. That's just as well, because back then a number of us students didn't think too much of it. There was a lot of theory, most of it entirely divorced from practice, and every morning there was a main hall lecture on topics such as the futility of lectures.
Not that there weren't some good and dedicated teachers - there were - but there were ropey ones too. One in particular, I remember, gave every indication of having retired some years earlier, only bothering to come in occasionally to pick up his pay cheque.
Today's students on the one-year PGCECert Ed course have a much more integrated programme than the one we followed back in the 1970s, with teaching and classroom management issues much more to the fore.
I sit in on one of these practical sessions. Twenty or so student teachers are getting to grips with the knotty problem of supporting and tutoring learners.
First up is a case study: a failing student who wants nothing more than to leave college and never come back. Sadly, you aren't allowed to say, "Good idea chum and good luck for the future." Instead you have to come up with the questions you might ask, as the student's hypothetical tutor, that would save his soul - or at least lead him towards some "elaboration and reflective thinking" about his future.
Next there is a role play.
Paul gets into role as a stroppy teenager, Gary his long-suffering tutor.
In footballing terms, you'd have to score this encounter 10-nil to Paul.
Faced with a brick wall of adolescent non-communication, Guy's "pull your socks up young boy-me-lad" falls rather flat. "I don't think I did very well," Guy remarks ruefully as he returns to his place.
As an old hand, you know that it's useful for them to do this sort of thing. But you can't help reflecting too that it's a bit like a group of Second World War pilots preparing for a raid on Berlin by sitting in a wooden cockpit while others jump about shouting "bang!".
You wonder also if they're being prepared for some of the other realities of a career in modern day FE. Are there practice sessions on things like pigeonholing your friends and droning on for hour after hour about how overworked and underpaid you are? Or a role-play where you're taught to walk into the staffroom on a wet Monday and declare: "I hate everything about my life!"
I shouldn't have worried. When I meet with a group of the students later they spend a lot of the time moaning; so it's clear they're already well adjusted to the realities of FE.
To be fair though it's not all complaints that I hear from the class of 2005. Indeed they all have pretty much that mix of idealism and cynicism you can find in any staffroom.
Why, despite all its drawbacks, do you want a career teaching in FE, I ask?
Christine, who has returned as a mature student in her forties, sums it up thus: "I just wanted to pass on my love of learning to others."
Debbie, back in education after serving her time in a routine banking job, adds: "I left school at 16. I had no qualifications. I hated teachers. I hated learning. Now I want to teach people who are like I was. Give me a challenging kid, and I'll take the challenge."
But oh, those moans. No doubt we grumbled in just the same way back in the 1970s. But still, there are a lot: the written work is hard; the support is not always there; their course has "no relation to the real world". Then there is the tyranny of the lesson plan: "Everything," one student complained, "absolutely everything, revolves around the lesson plan!"
Most of their complaints, however, are to do with their teaching placements. For Joan it is making the transition from student to teacher that has proved to be problematic.
"I'm not a morning person," she says. "Now I have to be in college every day at 9 o'clock."
Joe, who considered a career as an academic before plumping for FE, is frustrated at not getting to teach his real subject: history. "You're expected to teach things that are not your specialism. You're being asked to teach subjects you know little about."
Oh dear. Don't they realise this is what it's going to be like for the next 30 years? You want to take A-level politics, but instead they give you general studies. You're a hotshot accountant? How about a spot of numeracy key skills?
Last word goes to Christine, speaking plaintively about what it has been like teaching her first "live" class. "It's like giving birth. You look forward to it, but you don't know what it'll be like.
"Then you find it's incredibly painful and you resolve never, never to do it again."