David Eaglesham, general secretary of the Scottish Secondary Teachers’

Association, hopes to rouse his members at their annual congress in Coylumbridge with the rallying cry: “Education is far too valuable to give over to those who only seek to enrich themselves.”

In a gloomy speech, warning of the potential impact of deregulation, automation, casualisation and privatisation, he predicts that the outlook for teachers’ pay is not promising, based on Organisation for Economic Co-operation and Development economic forecasts.

“So far, the work of agencies in providing supply teachers is about as far as the private sector has invaded the direct provision of education,” he said. “Soon this will change as the analysts get to work on the algorithms for teaching tasks.

“More and more analysis will lead to greater and greater opportunity for alternative providers to supply the market. Producing the same final product (or pupils as we used to call them) at a lower cost using automation or lower skilled workers is the direct consequence.”

Meanwhile, the union’s president, Albert McKay, concentrates his fire on indiscipline with a warning that repeated short-term exclusions do not deter disruptive pupils and simply undermine teachers’ attempts to maintain classroom discipline.

Classroom teachers have a better understanding of discipline problems than senior management, he says, in a call to heads to give their staff more support.

Moves to tackle indiscipline would give a voice to the majority of well-motivated and co-operative youngsters denied learning because of a small, but significant, minority of their peers, he says.

“There are some worrying trends,” Mr McKay says. “More than 10 per cent of those barred last year had been excluded more than three times during the session. Yet there were fewer than 300 permanent exclusions - and extra dimensions are appearing, with a small but increasing number resulting from the misuse of mobile phones and websites.”

He will tell the conference: “Serious aggressive incidents between pupils do happen occasionally, but violence towards teachers is rare. Headteachers have a far more positive perception of discipline issues than teachers, support staff and pupils.”

He says that “the negative effect of poorly-motivated and disruptive pupils, for whom repeated short-term exclusion presents little deterrent, will continue to undermine the ability of teachers to uphold classroom discipline, damaging the experience of the majority and causing irrevocable harm to their own life prospects”.