The union blames parents for the behaviour of pupils

The NASUWT (National Association of Schoolmasters Union of Women Teachers) called on parents to be responsible for children's behaviour in school.

Scottish president Ian Clydesdale said the number of teachers slapped, kicked and spat on by pupils was increasing.

Last week the president of the Scottish Secondary Teachers' Association said that teachers did not have the tools to control classroom behaviour.

Speaking ahead of the NASUWT conference at Seamill Hydro Hotel in Ayrshire, Mr Clydesdale said: "I am very worried about the prospects for teaching in Scotland.

"If indiscipline and classroom disruption are not tackled head-on, we will lose more long-serving and long-suffering teachers through illness, particularly work-related stress.

Better prospects

"New teachers realise there may be better prospects of promotion and salary south of the border."

He said the union believed putting teachers first was the recipe for success in education, adding parents must be held to account for their children's behaviour.

Last week, the SSTA's Alan McKenzie said many staff concealed problems to protect the reputation of their school.

At the union's annual conference in Peebles, he called on ministers to state what was acceptable behaviour and to give more encouragement to exclude certain pupils.

A Scottish Executive spokeswoman said Education Minister Peter Peacock had made tackling indiscipline a priority.

Teacher shortfall

Meanwhile, up to three classes at a time are sometimes taught together because of a teacher shortage, according to a survey by the SSTA.

The secondary heads association which carried out the research, is calling for urgent action to tackle the shortfall.

The survey was carried out one week in March during the run-up to Standard Grade and Higher exams.

The executive said that any shortages were down to the way local councils managed staff.

The education authorities said the survey was anecdotal and not representative.