The full-time return to school in September for all pupils in England will be based on keeping year groups apart in separate "bubbles".
The Department for Education is expected to confirm safety plans based on reducing contact, rather than social distancing.
For GCSEs and A-levels, most pupils will be expected to continue with all of their intended subjects.
Attendance will be compulsory, with the threat of penalty fines for parents.
The rules for how schools will operate in the autumn are to be published on Thursday - although much of the detail was revealed in leaks earlier this week.
The safety plans will be an expansion of the "protective bubble" system already used in schools - in which classes or year groups are kept apart, with separate starting, finishing, lunch and break times.
The idea is to minimise the points of contact that could allow infections to spread - and does not primarily rely on enforcing social distancing.
As the Education Secretary Gavin Williamson said this week: "It's "not about one metre, it's not about two metres."
But it also means if there is an infection - either in a class or a year group - that all the children could have to be sent home.
Mr Williamson is also expected to outline the arrangements when he hosts a press conference at Downing Street in the afternoon. It will be the first government coronavirus briefing since ministers stopped providing their daily updates on the crisis on 23 June.
What are parents saying about the plans?
"I am a parent, and will not be sending my child back to school, if it is not safe to do so," Anthony told the BBC, when draft plans were revealed this week.
But Kirsty said: "Everything has got to start to go back to some sort of normal sooner or later. It's worrying but I think children need the stability of school and the social aspect of seeing their friends."
A primary head teacher got in touch to say: "This seems achievable if a little complex… Please remember all schools are different- trust the staff in that school to do it right."
Image copyright Getty Images Image caption Parents have raised questions about how pupils will stay apart on transportThe issue of transport to school was raised by a number of families - with questions about how that would work with "bubbles".
"Living in a rural area, my sons get a three-carriage train to school with 70 other boys and girls across all secondary year groups (and Joe Public)," wrote Iain.
"Moving start times by 15 minutes here and there will make no difference to the train they catch in the morning - so how do you 'bubble' that?"
"Transport to and from school a real concern too, packed like sardines on school buses, with no additional funds for more buses. Where will the funds for cleaning come from?" said Geraldine.
Another highlighted that families could have worries about relatives. "Some grandparents live with their children and grandchildren. Some of us parents are at higher risk than others," said Ade.
"The government have made everything blurred and while there is no vaccine the risks are still huge. I'll keep mine off until I'm sure of safety. Fine me or whatever - I'm looking after my family," said Eddie.
But Ian said: "Just send them back as normal and let them get on with it for goodness sake."
Sticking with all GCSEs and A-levels
The plans for returning will also recognise that pupils need to catch up after many months out of school.
This is likely to mean a "modified" timetable for the first term, with an emphasis on the core subjects of maths and English, and a regular curriculum might not return until later in the year.
Image copyright Getty Images Image caption Most pupils will be expected to carry on with a full range of GCSE and A-level subjectsBut for pupils taking A-levels and GCSEs, the expectation is that the full range of subjects will continue to be taken.
A later leak published by Schools Week suggested a subject would only be dropped in "exceptional circumstances".
In terms of safety measures, masks are not expected to be worn either by pupils or teachers.
But there will be regular routines of hand washing and desks will be arranged to children face forward, rather than facing each other on circular tables.
And the education secretary has promised a comprehensive track and trace system will be in place.
Attendance will be compulsory - with confirmation on Monday that penalty fines can once again be issued to parents who do not send their children back to school.
Although head teachers, who would refer absences to local authorities, have said they would rather build up trust in the school safety than begin by issuing fines.