Education Minister Kirsty Williams posted a video message on Twitter to say she hoped pupils enjoyed catching up with classmates and teachers on Monday.

An app is being used to give teachers, pupils and parents guidance on the school day and how to deal with issues around social distancing in the classroom and playground.

Jane O'Leary, of Vale of Glamorgan council, said: "It's a good way of showing pupils and parents that everything's being considered and it's safe to come back."

Other schools and councils have produced their own videos.

Ms O'Leary said coronavirus had presented big challenges for the council's 60 schools around transport, meals, hygiene and classroom logistics but the pieces were in place to provide a "safe and welcoming environment for staff and pupils".

Schools of all sizes have had to reorganise to reduce the infection risk.

Ysgol Gynradd Cerrigydrudion, in Conwy, has set up one classroom in the school hall, while others will have a maximum of six pupils in each.

But online lessons will also continue, and they are looking ahead to the likelihood of the school experience being "blended learning" for the considerable future, beyond September.

The village primary school normally has 80 children but now can admit a maximum of 26 pupils at a time, which includes children of key workers.

"Our plan will hopefully allow a connection with each child that wishes to come back to school," said head teacher Eirlys Edwards.

"And, of course, we respect the wishes of parents who don't want their children to return to school but we're aiming to keep in contact with them with live streaming as well.

"Hopefully this will be a warm-up, to prepare them for September, to return confidently."

Sarah Greenslade, schools convenor for Cardiff for public service union Unison, said it was “important” that children returned to school but health and safety had to remain paramount.

She said staff, including cleaners, catering and administrators, were “anxious” about catching the virus.

“September would have been more feasible and we would have known exactly where we stand then with the virus,” she told Radio Wales Breakfast with Claire Summers.

Paul Davies, a former headteacher and now governor of West Mon Comprehensive School in Pontypool said he would have preferred to have had “targeted year groups” such as children making the transition to high school and GCSE pupils returning to school ahead of the September restart.

He said children would remain in a “learning bubble” and with the same member of staff all day.

But he said Monday’s weather could affect plans to have children spending more time outdoors.

“It is not particularly helping the situation that many children are going to find themselves in today,” he said.

Teachers are feeling "excited" but "anxious" as pupils return to the classroom after the "longest break ever", a head teacher has said.

Year 7 pupils are returning to Ysgol y Grango, in Wrexham, from today, but classrooms will look very different with social distancing and safety measures.

Head teacher Stephen Garthwaite said pupils would have staggered starts and breaks, work in very small groups of just eight, and be with one teacher all day.

He told Radio Wales Breakfast with Claire Summers: "We are certainly excited about seeing them back in school, and I think it's a really good opportunity to catch up, to refocus them and re-engage them in the work that they've been doing at home.

"Things are very, very different, it's not the school we left, so there is a degree of anxiety and apprehension but generally we are very excited to see the pupils again."

Limited numbers of pupils will be allowed back at a time over the next three or four weeks to "check in, catch up and prepare" ahead of what has been called a "new normal" from September.

All schools have social distancing restrictions in place due to coronavirus.

So how have schools been preparing to reopen?

From today pupils in most parts of Wales will begin to return to the classroom for the first time since lockdown began.

While some children, those classed as vulnerable and children of key workers, have been able to go to school, many will not have seen their teachers face to face since March.

Now, under a phased return, pupils will go back to classes for a number of hours over the next three to four weeks to "check in, catch up and prepare" ahead of what has been called a "new normal" from September.

But with social distancing measures in place, and only a third of pupils back in school at any one time, this is a very different environment than before the pandemic hit.

Welcome to our live coverage of the coronavirus pandemic in Wales on the day that pupils can start to return to classrooms across the country.