His first play, The Jesuit, about Scotland's anti-Reformation martyr John Ogilvie, was premired in 1976 when Campbell was writer in residence to Lothian schools.
"I was appointed just before regionalisation," he says. "I was the first writer to be appointed to an education authority, Edinburgh at that time, on a full-time basis, and they kept me on until 1977, when I finished my term as director of the Lothian Young Writers Project. We produced an anthology of pupils' work but, in time-honoured fashion, the region decided they couldn't find the money to have it published."
Born in 1940, Campbell has been visiting schools for more than 20 years and says he has noticed a difference in the attitude of teachers.
"They may be more positive towards Scottish literature in general now, but back in the Seventies, I got the impression that teachers just lived for their work. For whatever reason, I feel that enthusiasm has largely gone. Teaching's less a way of life now.
"I think Scottish teachers are more like their English counterparts, or at least the ones I met giving readings in stockbroker-belt schools years ago. It's just a job to many of them - though Scottish teachers aren't as distant or as time-serving as many of the English ones I met."
Campbell has visited schools all over the country with the exception, so far, of Shetland. "The main value of a writer visiting schools," he says, "is in the form of bearing witness, in making kids realise that writing and literature are things that exist for their own sake, independent of school.
"It makes literature more real. It's also the case that often the pupils who respond to a poetry workshop are not the
academic ones. In my experience the ones who responded in the main weren't academic."
Although born in Caithness, where his play The Widows of Clyth is set, Campbell was schooled in Edinburgh, at Craiglockhart primary, where Norman MacCaig was one of the teachers, and at Boroughmuir where Sorley MacLean was principal teacher of English.
"My schooling didn't inspire me to write at all, but the idea that poets were real people and not simply names in a book was something I learned and that's one of the few benefits I got out of my education."
He describes MacCaig as sometimes "radical" in his teaching methods, giving commentaries on silent films in the classroom or indulging in Gaelic mouth music and teaching about Celtic culture, while MacLean was "so intense and charismatic, such a good performer".
Campbell's education was seriously interrupted through illness. He didn't start secondary school until he was 13, and didn't leave until he was almost 18. "I had jaundice, impetigo, pleurisy, just about everything. Spending long periods in bed, I became interested in reading and began wanting to write," he says.
Serving as a bank apprentice for three years, Campbell then upped sticks for London, where he worked at various jobs while pursuing his writing, and became involved in amateur dramatics. Returning to Edinburgh, and beginning to write poetry in Scots, he worked as an engineer at Parsons Peebles. A haphazard education for a writer?
"There's no way really to educate a writer. I remember once Ian Hamilton Finlay saying to me that if I wanted to be a writer, I should go to Canada and be a lumberjack. I suppose I did the equivalent of that in non-career jobs in London - like being a waiter and store detective.
"Most people can write. That's not the problem. The problem is whether you want to and whether you've got anything to write. You need to gain life experience. And it's not the sort of job where you proceed upwards by degrees. You'll always get knockbacks and rejections. It's not the best career to pick."
A founder member in 1970 of The Heretics, a group of poets and musicians who read and performed regularly in Edinburgh pubs, Donald Campbell took inspiration for his poetry from Scots writers such as Hugh MacDiarmid and Robert Garioch.
His own adult writers' workshops have had their moments too - such as having to eject a persistent flasher - "a total nutter," as he puts it.
He has just completed a new play, The Herring Queen, yet to be produced, and has been commissioned by the Edinburgh Festival's education department to create a new work celebrating 50 years of the festival. Entitled Festival Shock, it is due to be premired in June.