The Scottish independence referendum ignited teenagers’ interest in politics, inspiring one of the most clued-up cohorts of young voters in the world.

But new research shows that many teachers, far from helping young people get to grips with one of the biggest events in Scotland’s history, were effectively banned from discussing it.

Now a parliamentary committee has called for measures to ensure that young voters never again face such restrictions when discussing politics with teachers.

Pupils and teachers alike were unhappy about being prevented from talking about the referendum in the weeks leading up to the 18 September vote, a period known as “purdah”.

“Restrictions which some education authorities placed upon schools were overly restrictive during the purdah period and acted to restrict the ability of 16- and 17-year-old voters to discuss the issue in school and in particular with their teachers,” states the Scottish Parliament’s Devolution (Further Powers) Committee.

Its report examines the rules enforced by the country’s 32 local authorities, and finds that pupils around the country were treated very differently during the referendum campaign.

The final weeks of the campaign were when pupils “had become most engaged with the referendum” and sought to explore the issues with their teachers, the committee finds.

But while some students continued discussing issues connected with Scotland’s constitutional future until the end of the campaign - Clackmannanshire even held a debate in the week of the vote - referendum-related activities were not permitted by several local authorities from the moment schools broke up for the summer.

Fourteen local authorities placed restrictions on schools during purdah - a period that officially began 28 days before the vote but which was interpreted in various ways. Those restrictions tended to mean that no referendum-related activities were allowed at all.

For several authorities, the ban kicked in at the end of the 2014-15 session. In Angus, no activity related to the referendum could take place within schools at all; in Highland, teachers were restricted to answering basic factual questions from students on subjects such as where and how to vote.

Even before the summer, there were disparities in how councils handled the teaching of the referendum in schools.

In West Dunbartonshire, a school was granted permission to allow pupils to wear badges supporting the Yes and No campaigns, as this was seen to encourage “political awareness and participation”. In Argyll and Bute, however, any symbols and slogans that fostered rivalry were deemed unacceptable.

Almost all authorities encouraged schools to hold debates at some stage. But in one (Renfrewshire), referendum debates were not permitted on school premises, while two (North Lanarkshire and West Lothian) advised against the involvement of “external participants” such as MSPs.

In his evidence to the committee, Scotland’s electoral commissioner John McCormick acknowledged that different approaches were taken around the country. “Some people saw that as inconsistency, while others saw it as matching the needs of individual communities,” he said.

The committee has called on Education Scotland and local authority representatives to review how rules should be applied so that young voters in future elections “are able to discuss the issue freely in school, in particular through discussions with teaching staff”.

John Stodter, general secretary of education directors’ body ADES, said there was a “fear factor” in many local authorities, which had taken a “cautious approach” in order to avoid “getting it wrong in an extraordinarily political time”.

Authorities “could do better” with further national guidance and support materials, he added.

However Mr Stodter stressed that Scotland’s young people were getting involved with politics to an extent that had few parallels in Europe. This view was borne out by University of Edinburgh research this week, showing that 65 per cent of 18- and 19-year-olds in Scotland plan to vote in May’s general election, compared with 34 per cent in England (bit.lyVotingViews).

The Scottish Parent Teacher Council was “pretty clear” that the enthusiasm around the referendum should have been harnessed in schools to energise different parts of the curriculum, according to its executive director, Eileen Prior.

“We expressed our disappointment last year that more schools had not embraced the opportunities it presented,” she said.

An Education Scotland spokesman said the government would consider the report’s recommendations.

“We are committed to helping educators develop young people’s political literacy to the full and offer a host of resources on our website to help pupils participate fully in the democratic process,” he added.

`We can present views without bias’

“In the run-up to last year’s referendum, there was certainly a fear among Scotland’s councils that they should not be seen to influence pupils in any way,” says Stuart Clark, who teaches modern studies at Perth High School.

But this was misplaced, he adds, with “very few” complaints of teacher bias being reported.

Mr Clark believes schools have a duty to improve “political literacy”. He says modern studies teachers do this regularly and are “well used to presenting political views in a manner that would not be construed as showing bias”.

The achievement of the referendum in connecting people with politics clearly extends to young voters.

“I have witnessed a noticeable rise in political understanding and debate, mostly stirred by views on the referendum,” Mr Clark says. “Many of our senior pupils are now party members, which would have been a rare occurrence just a few years ago.”