Scotland's archetypal nationalist schools onslaught since the 1980s is taking spot with a one-day walkout by teaching staff.
Pupils astatine astir each superior and secondary schoolhouse and galore assembly nurseries is affected by the concern enactment implicit pay.
A revised wage connection connected Tuesday was rejected arsenic "insulting" by unions.
But Education Secretary Shirley-Anne Somerville said their demands for a 10% wage emergence were "unaffordable".
A caller wage connection from leader Cosla - which would person seen rises of up to 6.85% for the lowest paid - was fair, Ms Somerville said.
The Scottish schoolhouse strikes - by members of the Educational Institute of Scotland (EIS) and the Association of Head Teachers and Deputes Scotland (AHDS) - travel amid concern enactment crossed the UK connected Thursday.
Strikes are taking spot astatine 150 universities arsenic workers from the University and College Union (UCU) protestation astir pay, moving conditions and pension cuts.
Royal Mail unit are besides returning to picket lines for 10 much onslaught days astatine the postal service's busiest clip of the year, aft talks ended without agreement.
Picket lines
During the past nationalist onslaught by teachers successful Scotland successful the mid-1980s, it was uncommon for schools to adjacent completely.
Students could inactive be lessons with teachers who were members of different unions.
The EIS present represents astir 80% of the country's teachers and its actions are closing astir each primary, secondary and further enactment needs schools. Only a fistful of superior schools successful Orkney and Shetland volition stay open.
Many aboriginal years learning centres and nurseries are besides affected.
Teachers volition beryllium connected picket lines extracurricular schools and astatine rallies successful Aberdeen, Dundee, Glasgow and Inverness successful the morning, and extracurricular the Scottish Parliament successful Edinburgh during the afternoon.
And it said superior teachers planned to onslaught connected 10 January and secondary teachers the pursuing day, with further concern enactment successful February.
The Scottish Secondary Teachers Association and NASUWT program to onslaught connected 7 and 8 December, starring to closures of immoderate schools and disrupted timetables successful others.
Today is the time neither the Scottish authorities nor the EIS national hoped they would ne'er see.
This is the archetypal nationalist teachers' onslaught successful Scotland since the long, bitter quality of the mid-1980s.
The EIS and the different unions anticipation much strikes tin beryllium avoided and that contiguous volition beryllium a one-off.
But uncovering the wealth to springiness the unions a 10% wage emergence would mean immoderate precise hard choices for councils and the Scottish government.
The acquisition interaction of a one-day onslaught volition beryllium precise constricted successful itself.
But it comes arsenic schools proceed to retrieve from the interaction of the pandemic. The nonaccomplishment of immoderate teaching clip tin ne'er beryllium a bully thing.
It besides means that attraction which should beryllium connected raising attainment oregon helping pupils who mislaid retired during the pandemic volition alternatively beryllium focused connected balancing retired the interaction of disruption.
EIS wide caput Andrea Bradley said the national had been "forced into this strike" aft months of talks with Cosla, the councils' umbrella body, and the Scottish government.
"They person offered a bid of sub-standard offers that autumn acold beneath the complaint of ostentation and acold abbreviated of the justifiable expectations of Scotland's hard-working teaching professionals," she said.
Teachers had reacted with "great anger" to the latest connection from Cosla, Ms Bradley added.
"Their overmuch self-lauded 'generous and progressive' connection is really worth, connected average, an other 71p per week to Scotland's teachers compared to the antecedently rejected offer. For astir teachers, determination is nary betterment astatine all, arsenic 80% of teachers are inactive being offered 5%."
Parents' representatives said strikes could contiguous problems for families.
Leanne McGuire, from Glasgow City Parent's Group, said schoolhouse closures would beryllium peculiarly hard for azygous moving parents, those without a enactment web and children with further enactment needs.
"Those pupils truly thrive connected regular and erstwhile that regular is breached past it tin origin them a batch of distress, which past successful crook causes a batch of accent for parents," she said.
Ms Somerville said she was "very disappointed" that onslaught enactment would disrupt children and their families.
She told BBC Scotland's The Nine that a 10% wage summation was "unaffordable for the Scottish government".
"We person a fixed fund that is already afloat utilised for this year, truthful to bash thing that would summation the solution that we person connected this would mean that wealth would person to travel from elsewhere."
In a abstracted dispute, unit astatine 17 Scottish universities are expected to locomotion retired on Thursday and Friday and connected 30 November.
About 8,000 workers successful Scotland are expected to articulation a UK-wide onslaught implicit pay, moving conditions and pensions.
The University and College Union (UCU) said the interaction would alteration betwixt institutions, but they expected immoderate tutorials and lectures to beryllium cancelled.