At a certain level in politics, the subjects you specialise in become the luck of the draw, or at least the whim of your leader. However, I suppose it was inevitable that eventually I would come to speak on education for the Scottish National Party. After all my wife is a teacher and so were both my parents.

I have absorbed the regurgitated chat of the staffroom at the dinner table for more years than I care to remember and frequently have stood silent at parties (or as silent as a politician can) while teachers swopped shop gossip.

For those who are not teachers, the longest period they are likely to have spent in contact with any classroom will have been when they were themselves at school. Accordingly, I decided early on in my tenure as Shadow Minister for Education to try to learn as much as possible about what teachers and pupils actually do some 30 years after I last sat in front of a blackboard.

In the past two years I have visited almost 100 schools of all varieties.

However, trailing behind the headteacher and sometimes not being allowed to speak to anyone else, I felt that I remained a step distant from reality.

The answer was to do a bit of shadowing and spend some time experiencing the daily challenges faced by some of those who actually have to work in education.

Where better to set the scene than in the school which I attended and which was also attended by my father, my aunt, my two brothers and my cousins? The green dome of Marr College still towers over Troon, though a quarter of a century ago it ceased to be a grant-aided school and is now merely one outlet of the South Ayrshire education department.

Re-entering Marr College was, however, more easily talked about than achieved. The problem lay in a passage I had written in a book published in 1998 in which I attempted to update Edwin Muir’s 1935 Scottish Journey. As Marr College was opened in that year, and as my father had been in the first intake, it seemed an appropriate place to write about. Alas, I found then a school crammed to the gunwales, whose fabric was deteriorating almost before my eyes and whose potential - as envisaged by its founders - was far from being realised because of lacklustre management and a chronic shortage of resources.

I said so in print and then, after I was elected as MSP for South of Scotland in 1999, I helped a group of parents and sixth year pupils protest at the downgrading of the physical education department in the school. Both actions were noted by the autocrats of South Ayrshire Council, who quickly decreed that I could never again visit the school, even as one of Ayrshire’s regional list MSPs. Instead, if I wished to speak to the headteacher, it had to be in the county buildings in Ayr, with an education department official present. My offence, as noted to me in writing, was that I had published an article “critical of the council”.

A flurry of correspondence failed to change the view of the Labour administration and my promotion to Shadow Minister for Education did not melt their resolve either.

Some former pupils, I reflected in an article for an Internet site, are invited to present prizes. I was forbidden to cross the threshold of the building!

It was the Internet, however, that was my salvation. The article was picked up by an American site devoted to all things Marr College which acts as a clearing house for former pupils. Many of them e-mailed me and wrote to South Ayrshire Council. After a while newspapers began to report the ban.

Eventually it was rescinded, or at least lifted for long enough to allow me to visit one more time.

Trudging the familiar old corridors in the company of the headteacher and the convener of South Ayrshire’s education committee (sent to make sure that I did not misbehave again), I still found a shortage of resources.

Certainly the school has a fine computer department, some new cookers in the home economics department and it is even replacing the original seats in the hall, courtesy of a fund-raising drive by former pupils. However, a school built for 400 pupils, and with an annex added in the mid-Seventies that might take another 400 at a pinch, still contains 1,200 young people.

Every available space is used and that includes a number of spaces that should be available for something else. The headteacher’s office is the former medical room. The magnificently proportioned library under the dome is an overflow staffroom, sprinkled with plastic chairs. Cruellest of all, the gloriously proportioned mausoleum of an entrance hall, complete with bust of the coal millionaire Charles Kerr Marr, resembles a junk shop.

Some of the “junk” is the remains of a fine collection of art works and historic objects which originally belonged to the first chairman of the governors, Sir Alexander Walker (of whisky fame), and which featured in the school museum cases (yes, in my day it had its own museum!).

Understandably, the Marr Trust, which still owns the building and grounds and continues to give bursaries to pupils going to university, is nearly always at war with the school regime over issues such as these.

The school’s physical deterioration has not been accompanied, surprisingly, by an educational one. Scottish Qualifications Authority exam passes are well above average and 60 per cent of all leavers go on to higher education: this is one of the highest percentages for a local authority school in Scotland.

Despite cutbacks in the PE department, the school still excels on the sports field. Its old motto of Hic patet ingeniis campus - Here lies a field open to the talents - may have been superseded by the modern mission statement that is printed on the front of the school profile, “Striving for excellence in service to the community”, but the school does manage to live up to its ambitions, despite the problems.

Troon is an irredeemably middle-class town (although there are pockets of deprivation) and it is a Mecca for upwardly mobile commuters. As gaining a place in the school from other parts of Ayrshire is now virtually impossible, it is more than likely that people move to the town simply to take advantage of what Marr College offers. That will inevitably drive standards up.

But there is something else at work. The motivated staff - again, despite the disadvantages - is not unaware of the history and traditions of the school.

Marr College may have inevitably moved on from its semi-independent status but there is something about the building and grounds that demands at least an attempt to aim high. Such efforts take place elsewhere, as I have regularly seen, and in more difficult circumstances but in Troon the results speak for themselves.

The school is also a noticeably more relaxed place than it was 30 years ago. All schools probably are but here, while some of the best of the past has been retained, some of the worst - rigid and unthinking discipline, mock public school structures - has, fortunately, been discarded. It is certainly more socially inclusive.

In my last year at Marr College I worked on the school magazine. There is a photograph of the magazine editorial board of that year which has been regularly leaked to newspapers by another Marr College former pupil, the broadcaster Tom Morton. It shows me sitting in a dustbin. In a sense that was the fate of pupils who weren’t academic or didn’t come from families that forced the pace and had high expectations.

The school perhaps did too little for them but that is not the case now.

There is more effort to make all young people achieve something. South Ayrshire and a more modern Scotland can be thanked for that.

I enjoyed my afternoon at Marr College. It brought back memories but it also raised some fresh questions about what education was and is.

Is success still largely a matter of background and aspiring parents or are policies aimed at social inclusion succeeding in breaking down the privileges of the few and advancing - at last - the many?

Is the shortage of resources in Scottish education endemic? If so, is it as fatal a disadvantage as we all believe?

What do pupils and teachers think of the education system they work in together?

I was not allowed to ask such questions within Marr College. However, a number of people elsewhere that I can shadow might answer them for me.

Next week: joining Archie Morton, director of education, Argyll and Bute