Parents and students are preparing for widespread closures of secondary schools on Thursday.
Members of the ASTI say strike action is still on the cards after they failed to reach a resolution with the Department of Education yesterday.
The teaching union is staging the the first of seven days of strikes this week, in a dispute over pay for new teachers.
Further talks will take place today and tomorrow between the and the Department and the union, which represents 17-thousand secondary teachers.
Fianna Fails spokesperson on Education Thomas Byrne, says both sides need to come back to the talks table with a view to resolving this ongoing dispute: