Children who go to school without a mask will not be sent home.
The Department of Education has issued new guidelines following the implementation of new rules around mask-wearing for third class and up last week.
The updated guidance says "it is not intended that any child will be excluded from a school in the first instance".
It says children shouldn't be left out of class without principals trying to talk 'sensitively' to parents who object to their child wearing a mask.
Last week, it said children in third class and above should be sent home for not having a medical reason for not wearing a mask.
Guidance has also been issued relating to mixed classes. If 2nd and 3rd class students are sharing a classroom, just the 3rd class students need to wear masks.
Separately free antigen tests have been announced under a new 9 million euro scheme for third level students.
Colleges will be able to apply for funding to purchase tests to be distributed on campus.