Deputy first minister says all pupils and staff must wear coverings in classrooms, corridors and communal areas.
Spray painted markings warning people "don't get too close" have appeared outside schools and nurseries.
The education secretary says the need to ensure social distancing means fewer pupils can be in school at the same time.
Nursery children, primary 1-3 pupils and senior high school students will begin phased return to the classroom on February 22.
Nicola Sturgeon will announce on Tuesday if pupils in Primary 1 to 3 and students in S4-S6 can return to the classroom.
The change should also apply on school buses, advisers to the Scottish Government have said.
The Educational Institute of Scotland asked members how difficult it was for those without a permanent job.
Research from the Poverty Alliance found the attainment gap starts in the early years of education and grows wider over time.
First Minister Nicola Sturgeon will provide an update to the Scottish Parliament later on Tuesday.
The Scottish Liberal Democrats say urgent measures are needed to offer catch-up support to pupils.
No primary one intake has been registered at Glencorse Primary School in Penicuik since 2017.
John Swinney says coronavirus cases need to decline in 'emphatic fashion over a sustained period' before all pupils can return.
John Swinney says it is 'premature' to give a definitive view on schools reopening ahead of a formal decision next week.
Remote learning is in place for the vast majority of pupils across Scotland until at least February 1.
Educators remain optimistic that parents, staff and pupils will bounce back from the new coronavirus lockdown.
Scottish Government acknowledged there remains a risk of further disruption due to the coronavirus pandemic.
UK's chief medical officers say 'very few, if any' pupils will come to long-term harm from coronavirus solely by attending school.
Schools have been given the go-ahead to reopen from August 11 and many local authorities have adopted blended learning.
This year's results based on teacher estimates after exams were cancelled due to the coronavirus pandemic.
First Minister Nicola Sturgeon will update MSPs on schools as well as any further changes to lockdown.
