All remaining secondary school students will return to school on April 12th.
The Department of Education has said all students will return to classrooms on that date.
"[It] will see the return of all children to in-school learning, including the first to fourth year groups at post-primary level", the department said in a statement.
Over 300,000 children returned to school on March 1st for the first time this year.
The first four years of primary school students went back to in-class learning, along with this year's Leaving Certificate class.
Special schools also returned to full capacity.
Meanwhile NPHET has suggested a rise in coronavirus cases among younger children was not necessarily linked to the re-opening of schools.
Professor Philip Nolan said on Thursday that cases among children have risen by between 40% to 60% since February 1st.
But he said it would not be fair to link the increased cases among younger children with the return to school – noting that there has been six times more testing of children since re-opening.
"The data I presented shows that the number of cases being detected today is 40% to 60% higher than the number of cases detected on February 1st and it is going to be a period of time before we are going to be able to understand precisely why we are detecting more cases now," he said.
"Are there genuinely more transmissions among children or is it a mix of more transmissions among children and more testing of those children because of this appropriately high level of vigilance?"
Health officials suggested an increase in people meeting up and going to work was behind the plateau in case numbers - and warned that it will be a "challenge" to get daily figures below 500.