The BBC's schools programmes were regulated, but its adult output was left to the corporation, advised by an advisory council. By contrast, independent television companies had to satisfy regulators on quality thresholds and quotas for children and adults alike. For adults, this meant so many hours of approved programmes a week in prime time, and so many hours during the day.
I was privileged to sit for some years on the adult advisory panels of the BBC and the Independent Television Authority. Good conversation, good lunches and, on one of the panels, better wine than I was used to.
You could see clearly the pressures educational broadcasting was under - to be moved to the margins of the schedule to make way for blockbuster movies, or high-rating quiz shows.
Sometimes, the boundaries of the educational and the educative were difficult to sort out. So, at the BBC, none of David Attenborough's visually rich and informative natural history programmes counted, since they were made by the natural history unit in Bristol rather than by the education department.
And we developed a family game trying to guess which eight-minute slot of the ITV morning magazine programme, This Morning, was the educational programme.
Another heated debate related to back-up material: was any programme that was supported by off-air material or a phone line automatically educational?
Meanwhile, wonderful and inspiring things appeared regularly on the screen. And the fact that ITV was obliged to screen programming on the mass channel in prime time meant the slots were kept safe on the BBC too.
Margaret Thatcher changed all that, with her determination to set independent companies free from regulation. The imminent threat posed by satellite and cable channels was, apparently, set to fragment the television audience in the early 1990s.
It is easy to believe people caught in the excitement of a new technology, as this year's dotcom mania showed. As it turned out, satellite and cable ended up aping the structure of the mass-channel terrestrial broadcasters for their flagship channels. Viewers, it seems, like a mixed menu of programmes.
Education needs a place on that menu because television reaches people free at thepoint of use in their own homes and, for many, quickens a mild curiosity into a decision to take an interest further. As Bridget Plowden memorably said, broadcasting is democratic - there are no reserved seats.
The power of television to change behaviour is perhaps best illustrated by the BBC's family literacy shorts, made to back a Basic Skills Agency campaign. One weekend of exposure prompted 300,000 people to ring for help, and family literacy found a permanent place on the adult curriculum overnight.
Once the prime-time quotas went from ITV, though thankfully not from Channel 4, educational programming on BBC1 was pushed to later on the schedules, then into night-time - where, astonishingly, it attracted a substantial audience of first-time viewers alongside those "time shifting" with the aid of a video recorder.
The 1990s have presented a conundrum. The distinctive role of educational programmes has been slowly eroded, while marvellous learning campaigns have been developed - from Second Chance and Brookie Basics to Webwise and Generation Sex, television has shown new ways of identifying and meeting the needs of new learners, often using the techniques of advertising.
It is encouraging, too, if unexpected, that regional independent companies have strengthened their education officer force over the past 10 years.
But the technological magicians are back in force. The same qualities once ascribed to satellite are now bestowed on digital and on-line programming.
The BBC has an innocuous-sounding consultation out on transferring all its schools output on to digital. Apparently, the same thing is to happen to the Open University programming, depriving the 2 million people who eavesdrop OU programmes each week of a learning opportunity.
And now there are rumours that the BBC will end its dedicated educational production capacity, and change the role of its education workforce.
If this is true, it is serious business. For all the high hopes for the University for Industry, it is still mass-channel television that can create the passion for learning best. And, while dedicated channels are great for aficionados, the struggle to widen participation relies on reaching and surprising the viewer who is not yet looking for learning. Without programmes on the main channels, at a time of day most people watch the box, it is going to be a stiff challenge.
Alan Tuckett is the director of the National Institute of Adult Continuing Education