As few as 11 debates on the independence referendum have been organised by Scotland's 364 secondary schools in the weeks before the vote - and in some authorities discussion has been banned altogether.
The news has prompted fears that local authorities are doing a "tremendous disservice" to pupils, eligible to vote from the age of 16, by not helping them to make an informed choice.
Some schools organised referendum debates before the summer but such activity has now become extremely rare. A TESS survey of all 32 councils finds that most are blocking debates involving Yes and No campaigners this term, especially during the "purdah" pre-election period, when local and central government is not allowed to make announcements.
Of 11 debates that councils said were taking place, four were in one of the least-populated authorities, the Western Isles - one at each secondary - and four others covered Inverclyde's six secondaries. TESS has learned of two schools holding debates in East Lothian and one in Midlothian.
In Highland, it emerged this week that a debate at Kingussie High School due to be held today had been cancelled. In a letter to independent MSP John Finnie, which Mr Finnie posted on Twitter, headteacher Ollie Bray said that he had hoped the debate would have "a profound effect on the political literacy of our school community" but that "the decision [not] to run the event was taken out of our control".
Perth and Kinross is organising a Question Time-style event on 2 September for 1,000 pupils, while a handful of councils said some pupils would attend a major BBC debate in Glasgow on 11 September.
Some councils may permit classroom discussions without outside speakers, but others have decided that the best policy this term is for schools not to engage with the referendum at all.
Angus said that "no activity related to the 2014 Scottish referendum should take place within schools". In North Ayrshire, "the council is barred from publishing materials relating to the referendum, which effectively stops schools from undertaking referendum-related activities after the summer break".
In a note to schools, Fife said that in the official election period, which started last week, "no activity related to the 2014 referendum on independence for Scotland should take place proactively within schools.We are legally obliged to observe this requirement". Fife teachers must restrict themselves to answering questions on technical matters alone, such as how to vote.
Advice for schools was produced last year by education directors body ADES, School Leaders Scotland, Education Scotland and the Electoral Commission. ADES policy adviser Bruce Robertson said it was up to local returning officers to decide how to interpret that advice, but that it was "very wise" to avoid debates during purdah. ADES general secretary John Stodter said councils were taking "a precautionary approach" as they were "very sensitive" to accusations of bias.
"I hope that neither the legislative requirement on councils nor any guidance produced through Education Scotland acts in any way to diminish the opportunities that 16- and 17-year-olds have for participating in the referendum and wider civic engagement," said Robert Macmillan, vice-president of the Scottish Secondary Teachers' Association and Fife principal teacher of social subjects. "To do so would be a tremendous disservice to our young people and our curricular requirement to help shape responsible citizens."
Susan Quinn, former president of the EIS teaching union and a supporter of the Yes campaign, described meeting several pupils from different schools at a Women for Independence event. Some said that teachers were happy to let referendum discussion flow, but other teachers felt they were not allowed to.
"I don't understand why [councils] would take a line that you shouldn't engage the young people in consideration of these issues - that is the whole point of education," Ms Quinn said.
Stewart Whyte, an Aberdeenshire history teacher and vice-chairman of Better Together in the area, said that the general attitude was that schools were "reluctant to get involved" in the debate after the summer but that most of his pupils had sought information online and had already decided how to vote.
On his council's stance, he said: "We're being advised to keep away from [the referendum] in case it could be misconstrued." Mr Whyte, who has stood for parliament as a Conservative, added: "I wouldn't have had a problem had there been more debates, but I understand why the decision has been made."
Eileen Prior, the Scottish Parent Teacher Council's executive director, said: "We have argued consistently that [the referendum] is a great learning opportunity which schools should engage in. Debates or hustings are, of course, only one means, but we would have expected there to have been more than 11."
East Lothian's Musselburgh Grammar will today hear from SNP and Green MSPs (for Yes) and Labour and Conservative MSPs (for No). The demand from pupils for such a debate was "incredible", said modern studies teacher Ruairidh Nicolson.
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