It is understood exclusions have also risen at most other secondaries through the new no-nonsense approach.

Teachers are now being allowed not to tolerate serious misbehaviour, which wasn’t always the case in the past, when pupil indiscipline was often swept under the carpet.

Head teachers and their bosses were reluctant to send home disruptive pupils in case it showed their schools up badly in performance tables.

The Scottish Executive also asked for exclusions to be kept to a minimum because of their policy of social inclusion and integration.

The Executive was forced to change its mind after being inundated with complaints from teacher organisations and parents.

The teachers objected that teaching was becoming impossible and their health was suffering through being forced to cope with disaffected, demotivated and disruptive young people.

Parents protested that their well-behaved children weren’t getting the chance to learn because lessons were being disturbed by tearaways.

Last year Scottish education minister Peter Peacock announced that teachers were now using the new freedom he had given them to ensure less disruption for the majority of pupils and to take a zero-tolerance approach to violent behaviour.

Today a spokesman for Dundee City Council said, “Exclusion rates at Dundee City Council secondary schools have been increasing. This is for a number of reasons, but also directly reflects the council’s intention that unacceptable behaviour from pupils will not be tolerated.

“Education convener Councillor Kevin Keenan and the education committee have both been absolutely clear that staff and pupils must be allowed to work without intimidation or disruption.

“The committee will consider full and detailed guidelines on the management of disruptive behaviour next month.”

Dundee education committee has already discussed moves towards a new approach to managing unacceptable behaviour in schools. The matter was to be considered again this month, but has been put back because of the amount of in-depth consultation.

The Scottish Executive’s latest study of school exclusion rates is due to be published tomorrow.