Schools urgently need off-site "behaviour" units to deal with unruly pupils, teaching experts have said.
The Standards in Scotland's Schools Act groups pupils together
The Educational Institute of Scotland (EIS) blamed spiralling indiscipline and an official policy of "inclusion" for pupils with behavioural problems.
Both, it claims, lead to difficulties dealing with uncontrollable children who constantly disrupt classes.
Education Minister Peter Peacock said he would look closely at the recommendations made by the EIS.
Schools are bound to group children together regardless of ability or learning difficulty.
The requirement was set out in the Standards in Scotland's Schools Act 2000.
But in a report out on pupil indiscipline, the EIS claimed it had made it virtually impossible to exclude disruptive children on a permanent basis.
Sandy Fowler, convener of the EIS indiscipline committee, said the effects for teachers were time-consuming, stressful and damaging for the education of other pupils.
"These challenges certainly require teachers to be more reflective about their teaching and about pupils' learning," he said.
"But they also call into question the level of support that they receive from school management, from local authorities and indeed from the Scottish Executive."
Mr Fowler, a teacher with 35 years' experience, added: "It is the responsibility of the Scottish Executive and local authorities to meet these requirements.
"The Scottish Executive should provide, as a matter of urgency, additional off-site behaviour facilities for children and young people displaying particularly challenging behaviour."
Such units would be staffed by specialist teachers or volunteers, he said.
Mr Fowler claimed all of Scotland's estimated 3,500 primary and secondary schools had been affected by indiscipline to some degree.
Mike Finlayson, director of Teacher Support Scotland, backed the EIS comments and said 90% of teachers thought indiscipline had got worse over the last five years.
He added: "Indiscipline over a protracted period of time, even at apparently low levels, can have a devastating effect on the health of individual teachers.
"This can lead to anxiety, depression and illness.
"The unique pressures teachers experience are still not recognised and support for them remains inadequate."
James Douglas-Hamilton MSP, Conservative education spokesman, said: "The presumption in favour of mainstreaming has created a number of new problems and power needs to be given back to teachers.
"At the moment they do not have powers to permanently exclude disruptive children from class.
"Teachers must be put back in control of the classroom."
Responding to the report, Mr Peacock said: "I want to see teachers everywhere benefiting from the experience and practices of the strongest leaders and most effective techniques.
"I also welcome the recognition that there is now an unprecedented level of activity dedicated to seeking solutions to these difficult issues.
"Nonetheless, I will look closely at their recommendations for the executive, many of which we are already working on or have made provision for, and I look forward to continuing this constructive dialogue with EIS over coming months."