The Covid-19 Response Minister said a week ago Covid was in 1 in 10 schools, it's now in one in five.
Gathering limits will now no longer apply to school activities such as sport when there are unvaxxed students.
Forty million face masks are being distributed. Teachers are expected to wear medical masks, but kids can use cloth masks. There will be back up supplies for children in schools, including smaller size medical grade, he said.
Portable air filters and CO2 monitors are also being dispatched to check ventilation.
More than 700,000 rapid antigen tests can be distributed by the Ministry of Education if schools need them to keep up staffing levels, Hipkins said.
It would only be in extreme circumstances that teachers would go into school under the critical workers scheme, using rapid antigen tests (RATs) instead of isolation. Such as if the school couldn't keep running without them.
Hipkins said retailers would also very soon be able to sell RATs.
"Rapid antigen tests are no guarantee, so we would only put someone in the school environment with that level of risk if we really had to."
He said overseas studies showed RATs could be missing one in five cases.
That was too risky for schools, so schools would first be expected to try to secure relief staff or take other measures to fill in for staff who had household cases of Covid-19.
On sports, Hipkins said they never intended children to be barred from playing sport if they were not vaccinated.
However, some schools were interpreting practices such as kapa haka and other school activities to require a vaccination pass.
He said any school activities would not need a vax pass for students. "We are just clarifying those rules to be crystal clear."
It was up to clubs to offer an unvaccinated option for children who weren't vaccinated.
"There's a degree of hesitancy around having unvaccinated people involved in those activities, they are worried other people won't take part if there are unvaccinated people involved."
However, he said when it came to school-arranged activities, children should be able to participate fully in school activities, regardless of whether they were vaccinated.
He said the Prime Minister had signalled restrictions would be eased after the Omicron peak, and so the club sport issue could be resolved at that point.
He said they did want children and teachers on-site as much as possible, but there would be situations where that was not feasible.
Parents would be subject to the same rules meaning unvaccinated parents could take part in school-arranged activities, but if it was out of school the vaccination pass requirements would apply to them.
He said it was possible there would be further advice on boosters for children in the future.
When the technical experts advised giving boosters to children, they were ready to do that.
He said boosters rates were high in the most vulnerable population - the elderly but the evidence around the impact boosters would have on infection and severity of Omicron in children was still emerging.
Blended learning, where some children were at home and others at school, was difficult and support would be provided in those situations, Hipkins said.
He said there was interest among teachers in having access to RATs, but not necessarily to be able to go into school if they had a household Covid case.
There were at least 5000 air cleaners available for the winter period, when ventilation was harder.
There would be some schools and rooms where ventilation was harder - and rooms where there was more risk, such as school staffrooms where teachers removed masks to eat and drink, and risked infections.
