Scottish schools have started to return from the Christmas holidays, and in some cases reopening has been reasonably painless.

Other schools have, however, achieved it by the skin of their teeth, and in a few cases, despite the best efforts of staff, it has not been possible. At Muckhart Primary in Clackmannanshire, for example, pupils will be learning remotely this week for Covid-related reasons.

Tes Scotland spoke to one secondary headteacher as he supervised two merged classes in the school canteen after an unprecedented number of teachers were unable to come to work. That head - who leads a school of around 1,000 students - was preparing to send out an email to parents telling them an entire year group would have to learn remotely today (Thursday) because staff absence was going to be too high for the school to be able to accommodate all children.

Background: What schools need to know about new Scottish self-isolation rules

Scotland editor’s view: Teachers should know how deeply appreciated they are

Quick read: Remote learning may be necessary in ‘hotspot areas’

It has long been the case that the bulk of Covid-related school absence has been caused by students and teachers having to self-isolate, and not because they themselves have actually tested positive for the virus.

First minister Nicola Sturgeon’s announcement yesterday about changes to the self-isolation rules was therefore big news - but is it good news for schools?

Ms Sturgeon said in a statement to a virtual meeting of the Scottish Parliament on Wednesday afternoon that positive cases - from midnight last night - would be able to reduce self-isolation from 10 days to seven days if they had no fever and two negative tests carried out on the sixth and seventh day, 24 hours apart.

Covid and schools: The softening of self-isolation rules

She also said that close contacts of a positive case - including household contacts - would no longer have to self-isolate if they were fully vaccinated or under the age of 18 years 4 months, in other words of school age.

Instead, Ms Sturgeon said, the fully vaccinated and the under-18s who were close contacts would be required to carry out daily lateral flow tests for a period of seven days; only if a lateral flow was positive would they have to self-isolate.

The general secretary of secondary headteachers’ organisation School Leaders Scotland, Jim Thewliss, told Tes Scotland that the changes to the rules were “a measured approach and sensible response to the situation we are now in”.

In recent days Scotland has recorded record-breaking numbers of daily positive cases, and staff absence is already putting a huge strain on public services such as the NHS - with schools also expected to suffer from a staffing crisis.

But EIS union general secretary Larry Flanagan told Tes Scotland that the union was opposed to any reduction to the self-isolation rules, saying they had already been watered down with pupils in the same class no longer considered close contacts after schools returned in August. He said the change could lead to “greater spread of Omicron” and therefore more staff absence, which, in turn, would be “disruptive to the continuity of education”.

Mr Flanagan also pointed out that uptake of lateral flow tests among secondary students had so far been low - the latest figures are considered to be an underestimate of actual uptake, but they show 23.6 per cent of S1-3 students have undertaken at least one lateral flow test since the start of the school year in August, and just 13.3 per cent of S4-6 students have.

He said it was “quite a big leap” for schools to take it on trust that school students would carry out daily lateral flow tests for seven days - especially in light of recent shortages of test kits.

In Parliament yesterday, Ms Sturgeon admitted that the changes “were significant and not completely without risk”. She also said that “Covid is significantly more widespread now than at any stage in the pandemic so far, and will almost certainly become even more so in days to come”.

But the first minister added that a balance had to be struck “between the continued importance of self-solation in breaking chains of transmission and reducing the disruption self-isolation causes in the economy and critical services”.

The impact of the changes, therefore, remains to be seen, but absence will remain an issue for schools - and some heads believe a tipping point has already been reached.

Jon Reid, headteacher of Larbert High School in Falkirk and president of School Leaders Scotland, wants the government and the Scottish Qualifications Authority (SQA) to move to the contingency plan that would involve teachers and students being given advance notice of some topics that will feature in exams. He argues that this would allow teachers to prioritise the work that they undertake with their classes.

Mr Reid said: “The perception is that schools are open, pupils are back and the teachers are here, but that’s not what is happening on the ground. The number of pupils whose learning has been disrupted either because they have had Covid, because they have been isolating or because their teacher has not been in front of them is pretty significant.

“We need to develop that understanding that schools are open but it is not business as usual, and it is likely to get worse in the weeks to come as pupils return and more staff catch Covid.

“It is unfathomable that the government and the SQA would wait until March to tell us if we are moving to scenario two when teachers could be prioritising the work now, instead of trying to cover the whole course.”

It may well be impossible, therefore, to accurately predict the twists and turns the pandemic will take over coming weeks an months, but clarity over the exams, heads say, would relieve some of the pressure on secondary schools at least.