Schools and all third level colleges have been asked by the Minister for Education, Dr Woods, to close today for the national day of mourning.
This will involve over 3,000 primary schools, 760 second level schools and up to 40 third level colleges closing.
Dr Woods said all schools and colleges should close "where possible" for the whole day.
Most schools are entering their second week of term, whereas most third level colleges have yet to open their doors so closing should not present difficulties.
UCD said its registration day scheduled for today has been postponed until September 17th.
Many students have been effected by the events in New York. An unknown number have been stranded at JFK air port trying to catch flights home.
Meanwhile the Irish Vocational Education Association (IVEA), the representative body for VEC schools, said it fully endorsed the Government's decision to hold a national day of mourning.
IVEA president Mr Brendan Griffin expressed his deepest sympathy to the families, friends and relatives of victims both in the US and in Ireland. Mr Griffin called for a national response in support of the day of mourning.
The IVEA's head office at Marlborough Road in south Dublin would close on today as a mark of respect, he said.