SEVERAL schools will shut down this week after taking unilateral decisions in the absence of clear direction from ministers.
Comprehensive guidance is due to be issued to principals this week.
Schools in the north remain open, in line with Britain, while they will be closed for two weeks in the Republic.
The executive is due to meet on Monday with ministers at odds over whether there should be a widespread lockdown.
Deputy first minister Michelle O'Neill said they must close immediately while first minister Arelene Foster said this could be counterproductive.
She later said that a shut down, when it happens, is likely to last 16 weeks - children would likely not return until after the summer holiday.
Principals have argued that it is not as straightforward, pointing out that closures can be reviewed on a weekly or fortnightly basis.
The leader of the Catholic Church in Ireland has written to education minister Peter Weir urging him to consider closing schools.
Archbishop Eamon Martin said the St Patrick's weekend provided a "clear window" for parents to make childminding arrangements ahead of closures, and for schools to make contingency plans.
With many due to close for St Patrick's Day anyway, some have decided to use staff development days as well this week and have told their pupils to stay at home.
They include Lurgan Model PS, St Scire's in Trillick, Co Tyrone, Seaview PS in north Belfast and St Joseph's Grammar School in Donaghmore.
Michael Allen, principal of Lisneal College in Derry asked the Department of Education to grant a minimum of two additional exceptional closure days "to help prepare resources as we face imminent longer term closures"
All classes at his school have been postponed on Monday.
"The current situation we face is like no other I have seen in my lifetime. My priorities at the moment are to protect vulnerable children, staff and family members, and to prepare learning resources for our pupils," he said.
"This is a ‘no win’ situation. Updates will be communicated to pupils/guardians and parents via text message, our website and social media pages."
Education expert Tony Gallagher from Queen's University Belfast said he was "massively impressed" by schools.
"Principals communicating clearly and frankly with parents; closing to allow time for teachers to work on online materials; sharing resources and expertise; keeping calm, working together and showing leadership," he said.
Responding to Archbishop Martin, meanwhile, Mr Weir said he respected his position, "particularly given the pastoral responsibilities he has on both sides of the border, and appreciate the sincere good intentions of his letter".
"I have a clear duty of care to the education of children of Northern Ireland, and above all to the public health of all our citizens. In discharging these duties in the current extremely difficult and fluid circumstances, I will follow the science and professional advice, to support the right interventions, which will have the greatest impact, at the right time," Mr Weir said.
"Consequently, I accept and support the guidance of the chief medical officer, Public Health Agency and the Scientific Advisory Group in Emergencies that now is not the right time to close schools in Northern Ireland. I will be seeking to make contact with the archbishop, to explain and discuss the matter directly."
