SCHOOLS are having to teach pupils National 4, National 5 and Higher qualifications in the same class because of teacher shortages, experts have warned.

The Scottish Parliament's education committee heard controversial "tri-level" teaching was a growing problem - with concerns it led to lower standards.

Last summer, The Herald revealed schools across Scotland had more than 700 vacancies just weeks before the new school year.

The research showed shortages in key subject areas such as science, maths, computing, languages and home economics, as well as in rural areas.

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William Hardie, policy advice manager for the Royal Society of Edinburgh, told the committee multi-course teaching was a particular issue in the sciences.

He said: "Whilst courses may have similar titles, a National 4 in physics will be very different from a National 5 course in physics, but quite often they will be taught together which can obviously impact on the quality of teaching if a teacher has got to teach quite different classes.

"Sometimes that can be exacerbated by having to teach National 4, National 5 and Higher in the same classes.

"This obviously touches on the difficulties of recruiting subject specialist teachers, particularly in the sciences and computing science, which means that in some schools multi-course teaching may well be the only way the school can timetable those courses to allow them to be run."

Professor Jim Scott, from the School of Education at Dundee University, said the extent to which tri-level teaching was now prevalent was a major concern.

He said: "It tends to be prevalent in minority subjects or in smaller schools, but it is a genuine issue. With the sciences it should be a no-no, but it does seem to be prevalent in quite a lot of the smaller subjects.

"It seems to be a growing problem. Some sources indicate this is down to local authority staffing levels, some of them indicate it is the headteacher or senior management team's view of the curriculum and some say it comes from the principal teacher who wants to do it this way to make space and time."

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Labour MSP Johann Lamont asked to what extent the requirement for multi-level teaching was built into teacher training to ensure staff were equipped for the practice.

Dr Alan Britton, senior lecturer in education at Glasgow University, said initial teacher education "did what it could" to prepare teachers for the different scenarios they would encounter.

He said: "We prepare them as best we can and if they are subject specialists in secondary then we will try to prepare them for the reality of multi-level teaching.

"Would any teacher actively choose to construct their teaching and learning in that way? The reality is that most teachers, if given a choice between multi-level teaching or not, they wouldn't want it."

The warnings come after a survey by the Scottish Secondary Teachers’ Association found 47 per cent of members were teaching classes containing pupils aiming at two different qualifications and a quarter had pupils studying three.

A separate study in 2017 by the Royal Society of Chemistry found 73 per cent of National 5 chemistry classes had pupils studying for other qualifications and 21 per cent of Highers being taught were multi-course.

Asked how well they felt able to support pupils in multi-course classes, 70 per cent of teachers in National 4 and National 5 classes responded either “not at all” or “not very well”.

MSPs also heard concerns over evidence given at the last committee meeting by Gayle Gorman, the new chief executive of curriculum and inspection body Education Scotland.

She said earlier this month that the link between an area's wealth and the number of Higher subjects on offer was not as big a concern as some thought.

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This was because extra government funding for schools in disadvantaged areas and "consortia arrangements" where pupils can travel to other schools to sit a wider range of qualifications were proving effective.

Mr Scott said: "I have to say I was surprised. I found myself wondering if I lived in the same educational world."

Mr Hardie added: "If Education Scotland is simply saying there is no link and not substantiating that then it may be an area this committee may want to follow up with them to see if they have data which shows a different answer."