The SA Premier has once again defended the decision to keep schools open in the state despite many parents remaining "confused" and "nervous" about the dangers posed by the coronavirus outbreak.

Key points: Premier Steven Marshall said schools would stay open in line with health advice

Premier Steven Marshall said schools would stay open in line with health advice Some parents remain "nervous" about the dangers of sending children to school

Some parents remain "nervous" about the dangers of sending children to school In Victoria, the school term has been brought forward to end on Tuesday

It comes as Victorian Premier Daniel Andrews yesterday announced the end of the state's school term would be brought forward by a week to Tuesday.

Yesterday, Prime Minister Scott Morrison also announced new measures with greater restrictions on movement across the country.

He said places like pubs, indoor sporting venues and churches would be closed by midday on Monday.

Despite the decisive action, SA Premier Steven Marshall this morning reiterated that South Australia was following health advice and keeping schools open.

He said he recognised that some parents would want to keep their children at home but urged them to take responsibility.

"If parents are going to take their children out of school, they do have a massive responsibility to keep those children safe and supervised," he said.

"And they also need to recognise that if they do this it's not a two-week requirement, these restrictions are likely to be in place for six months."

Parents are torn between keeping children home and sending them to school while schools remain open. ( ABC News: Tim Swanston )

Last week, a year eight student from Unley High School tested positive for coronavirus after contracting it from a teacher.

A student from Sacred Heart College and a Scotch College student have also tested positive.

Both schools were temporarily closed to allow for cleaning to occur.

Opposition Leader Peter Malinauskas said more clarity was needed for parents, especially if the State Government was going to use the Singapore education system as an example to follow.

He said Singapore schools had remained open but were taking the temperature of every child, every day, and had many other measures in place.

"If we're going to have schools open, let's put in place daily temperature checks for every child," he said.

"Let's make sure that every classroom gets access to basic hygiene products.

"Let's make sure there are staggered recess and lunch breaks. That we cancel assemblies, camps and other mass celebrations in schools.

"If we're going to keep schools open, if we're going to be different to 107 countries around the world that have closed their schools, if we're going to be different to Victoria and the ACT and point to Singapore as the model, then let's make sure that we're actually following it."

He said he sent his daughter to school this morning but was still nervous about the risks for both students and staff.

"One of the things we should do to massively alleviate some of the anxiety that parents are feeling, myself included, is put in place measures at schools that mitigate the risk," he said.

"If they're going to be open let's mitigate the risk."

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'I don't know if today will be their last day at school'

Many parents this morning shared their confusion around the measures in place in South Australia and admitted they didn't know what to do.

An Unley High School senior keeping his distance from other students. ( ABC News: Lincoln Rothall )

"I honestly feel a bit confused. I don't know what to think," one mother said.

"I think if we have the chance to stay at home, we should. Health is the most important thing now."

Another parent this morning said she had been having discussions with her husband about what best to do for her children's safety.

"I don't know if today will be their last day at school, if we should pull them out … it's all getting a bit scary," she said.

"My husband and I have been talking this morning about whether we just pull them out of our own accord and try to keep them as safe as possible.

"As of today, I'm working from home so I won't be going back to the office and that will be an option for us."

Although some parents remain confused, one grandfather said he thought the State Government was doing the right thing, for now.

"I feel that it's a good call at this point in time that parents have got a choice to leave their kids at home or bring them to school," he said.

"As long as the parents do the right thing as well with the children. If they keep their children at home and they shouldn't let them wander around and cause more problems.

"There's always a bit of apprehension. I do believe things will get worse but how worse I don't know."

'Impossible to ensure social distancing in classrooms'

The SA education union said the State Government should follow others in bringing forward school holidays.

AEU SA president Lara Golding has called for the closure of schools. ( ABC News )

AEU SA president Lara Golding said leaving schools open had made teachers feel anxious about workplace hygiene and social distancing.

"Their key concern is around their work health safety and ensuring that they have a safe workplace in our schools, pre-schools and TAFE," she said.

"It is mathematically impossible to ensure social distancing in classrooms at the moment and in the schools that plays out with children of all ages and in TAFE that plays out with adults in small spaces.

"And also concerns around ensuring that there's adequate hygiene facilities, enough soap and sanitizer and enough places for students to wash their hands."

She said sending students home now would help schools prepare for the months ahead.

"We believe SA should follow the lead of ACT and Victoria in bringing forward pupil free days," she said.

"This will enable time for schools to prepare materials and prepare for a range of different delivery options into the future."

Yesterday, the SA Government declared a "major emergency" and announced it would establish 12 border crossings where travellers will be required to sign a declaration about their health and ability to undertake mandatory self-isolation for two weeks.

It comes as South Australia recorded its 100th case of coronavirus at the weekend — an increase of 33 from Saturday.