Director General of Health Ashley Bloomfield and Secretary for Education Iona Holsted have answered the public's questions during a Facebook Live session.
Holsted said there was work underway to work out how many children would be going back to school to make sure schools were prepared.
What does the research show about Covid-19 in schools?
The principles for making workplaces safe were the same for schools and those were physical distancing, keeping groups small and keeping children home if they didn't need to be there, said Bloomfield.
Keeping students home would also help the country ease between alert levels.
"The work that all New Zealanders have put in over the last month and the small number of cases that we're seeing means that we can all have a high level of confidence as we go about our work in any setting."
The chance of a Covid-19 case coming through the school gate was very, very low, Bloomfield said.
Are there enough teachers?
Holsted said it was very hard to make any guarantees in a Covid-19 world, but planning was underway to ensure there were enough staff.
School communities should be getting in touch with families so there were no surprises on April 29 and that distance learning was going well.
Preparations were also being made for wider education workforce, including teacher aides and support staff.
In the event a school did reach a situation where there wasn't enough staff, Holsted said the Ministry would work with them to make sure their needs were met.
Teachers could be invited to work in another school and relief teachers were an option.
What health measures are in place?
Bloomfield said the safety of schools and ECEs would be "directly proportionate" to how seriously New Zealanders took alert level 3.
Anyone with any symptoms, even a sneeze or a sore throat, shouldn't go into an educational facility and they should call their GP or Healthline to see if they should be tested, Bloomfield said.
Parents should also be strict with keeping their home bubbles small and maintaining hygiene measures.
At school, students would be kept in small groups, there'd be as much physical distancing as possible and surfaces would be thoroughly cleaned, he said.
How important is hand washing?
Hand washing is a vital part of everyone's response, Bloomfield said.
If someone isn't sneezing or coughing, the only way the virus could be spread is if touches their face then touches someone or something.
Hand washing stopped transmission in that way.
"Hand washing is a fantastic thing to be doing because it's going to protect you not just from Covid-19 if it happens to be there, but of course against all those other infections.
"So this is a really important practise both at home and at the school and ECE setting," Bloomfield said.
How big are school bubbles?
Bubbles would be nine students and one teacher.
Bloomfield said those groups would remain the same throughout the course of alert level 3.
Schools were looking to move away from the classic "room 1" and "room 3" and would instead be creative about how they grouped children.
It's going to be school, but not as we know it, Holsted said.
Siblings in the same home bubble could play in the same school bubble.
What about children with special needs?
Holsted said there are a small number of students with high and complex needs, for example children at higher risk of severe illness from Covid-19, where public health measures required under alert level 3 cannot be maintained at school. Ministry staff have been working remotely with individual students during lockdown to support their learning at home, and will continue to do so.
"Most other students with learning support needs can attend school safely during alert level 3 if requested by their parents," she said.
"We are encouraging schools to think flexibly about how they can support these students using the resources they have at hand, keeping in mind that on-site learning is not operating as normal."
What temperature should the classroom be?
Schools and ECEs should be kept at least 18C because anything under that had an increased risk for respiratory illnesses, Bloomfield said.
Especially coming into autumn and winter, rooms should be kept at a comfortable temperature.
How do I give my kids assurance they will be safe?
Bloomfield said if every New Zealander followed the advice and did their bit, then our children and young people would be safe.
"This is a collective effort - it needs our efforts in the ECE or school setting but also in the home environment and in the wider community to protect them and to protect all New Zealanders."
Parents should keep their child home if they're sick and be strict about keeping their bubbles very tight.
Bloomfield said flu cases and respiratory illnesses had dropped to almost zero as a result of the lockdown and New Zealanders were almost as healthy as they'd ever been in that regard.
Can kids use the playgrounds?
Bloomfield said they would not be open.
On children using blocks, Lego and other classroom hard materials, Holsted said those would be cleaned regularly.
What happens if a student or teacher becomes unwell?
They should stay home and seek medical advice.
Bloomfield said testing gave them increasing confidence there wasn't wider community transmission.
Testing was one of the things the healthcare system was doing to ensure children and young people were safe, he said.
How do you physically distance young children?
ECEs weren't being asked to keep very young children apart, Holstead said they should instead be focused on providing a clean, safe environment "for children to be children".
What about early childhood centres refusing to open?
On many ECEs refusing to open, Holsted said they were working to make sure centres were safe and advice was going out about how they'd be able to do that.
Some ECEs were looking forward to opening, she said.
What about the staffroom?
Bloomfield encouraged school leaders "to be rigorous" about the staff rooms as they were potentially one of the highest risk areas.
Who is ultimately responsible for the safety of students and staff?
Boards were still responsible but there were also obligations for the Ministry of Education to provide advice to boards, Holsted said.
It would not be perfect, but it would be advice school leaders could give their school communities, Holsted said.
What happens at level 2?
Holsted said she expected all students to go back to school under alert level 2, unless they had vulnerabilities.
Stay home from school if you can - Minister
At a press conference today, Education Minister Chris Hipkins said under alert level 3, most children would be expected to continue with distance learning.
Schools would be open only for students who needed to be there. Education for students in Years 11-13 would continue remotely.
Students in university hostels, or flats could stay there, but those who had returned to their homes for the level 4 lockdown could not return.
At schools, cleaners and other staff would be allowed back to tend to the properties before the teacher-only day on April 28.
He cautioned it could take some longer than others to be able to reopen for students who needed to be there.
He said the Ministry had kept in close contact with Early Education advisory groups and that would continue.
More detailed advice would be released over the next week.
Hipkins said he was confident that schools would be able to operate at alert level 3.
Asked if teachers could opt out of returning to work because they were concerned about their safety, he said he did expect teachers "to do their bit".
He said those teachers who were in the vulnerable groups because of age or a condition, or lived with someone else in those groups, should talk to their schools about the situation.
Hipkins said keeping numbers at schools low was key. One of the elements being looked at to ensure the school bubbles remained tight was cleaning the bathrooms in between each group using them - a system of rostered toilet breaks.
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Are children at risk of getting coronavirus?
Bloomfield was asked at the press conference today about his advice that children did not pass on the virus, and referred to a WHO report which found that in Wuhan - and other countries since - very few cases were in children and there were no cases in which a child had passed the virus on.
He said in New Zealand, the children who got the virus had got it from others in their household.
Bloomfield said if there were cases that got into an ECE, keeping children in "school bubbles" should make it easy to trace contacts.
He said given the low numbers of new cases, and very low numbers of community transmission, the chances of the virus getting through the school gate in the first time was very low.
Nearly 650,000 households tune into educational broadcast
Hipkins said 649,000 people had tuned in during the first three days of the televised learning sessions, led by Suzy Cato.
"To all of the parents out there, my message to you is be kind to yourself. We are not expecting parents to completely replace the learning environment at home.
He said the Government was doing its best to limit the impact on children's learning.
He said about 400,000 more Kiwis would go back to work, but about one million people would still be at home. He urged parents to try to find other family arrangements to look after their children if that was an option - such as an aunt or relative.
He said if some schools could not meet the public health guidelines around distancing and hygiene, they would look at whether they could "spread the load" to other schools or ECEs.
It was easier to preserve bubbles in some places than others. Early learning services would get support.
He said one of the reasons the public health guidance was out there was because of the difficulties in having children maintain physical distancing.
That would rely on keeping children within the same bubbles, and emphasising hygiene.
What about NCEA?
Asked about support for NCEA students to ensure their year was not impacted, Hipkins said guidance was being provided to schools for children who had to miss some internal assessment or exams.
It was possible students could play catch-up next year, such as by finishing some level one papers next year while they were doing level two.
Hipkins said students could do some work at home, although that was harder for courses with practical components such as science.
It was too early to assess what impact it would have on overall educational outcomes, but he said the Christchurch earthquake had little impact on that year's outcomes.