SCHOOL staff are calling for smaller class sizes when teaching pupils with special needs such as autism and dyslexia.

The demand comes amid mounting concerns about the level of support available for vulnerable pupils as councils struggle with restricted budgets.

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Under the policy of inclusion, more pupils with additional support needs (ASN) are being taught in mainstream rather than special schools.

However, surveys have shown teachers are concerned the increase has led to rising indiscipline and a negative impact on the education of other pupils.

Last year, the Scottish Government admitted that not all children with learning difficulties in Scottish schools were getting the support they are entitled to.

Mike Corbett, a national executive member of the NASUWT teaching union, said one solution was to reduce class sizes where ASN pupils were placed.

He said: "Teachers want to do the best for all the kids in their classes, but increasingly with the inclusion agenda you are getting more ASN pupils in mainstream classes and there has been a concern about teachers having the right amount of time to address those needs.

"Up to now there has been resources put in to free up teachers or classroom and support assistants to be with pupils in this situation and that has been a help, but the big issue is that councils are now cutting those budgets."

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Mr Corbett said he wanted the Scottish Government - alongside the union - to devise a staffing formula that would see class sizes reduced where ASN pupils were present.

"If you have fewer pupils in your class as a teacher then you will have less marking to do and more time to prepare lessons for ASN pupils and more time to spend with all pupils."

Mr Corbett was speaking ahead of the NASUWT's annual general meeting which will discuss the call for smaller class sizes alongside other motions on ASN pupils.

One motion tells how it "deplores" the reduction in support for ASN pupils at a time when the Scottish Government has prioritised closing the attainment gap between rich and poor. Another states that resources are being diverted to support ASN pupils in ways "which may not be appropriate".

Under the 2004 Education (Additional Support for Learning) (Scotland) Act a statutory duty is placed on local authorities to identify, provide for and review the additional support needs of their pupils.

ASN covers pupils with a range of issues including learning disabilities, dyslexia, a visual or hearing impairment, language or speech disorders, autism and social, emotional and behavioural difficulties.

There are currently more than 140,000 ASN pupils in Scotland - some 21 per cent of the school population - but the numbers vary markedly between different council areas prompting concern from campaigners that thousands of pupils are missing out on support.

The Local Government Finance Statistics 2014 indicate that education authorities spend just over £4.8bn on education in Scotland. Of that £555m is spent on additional support for learning.