Pressure on secondary teachers increased last night with parents considering a protest march next week and the Minister for Education, Dr Woods, again ruling out any special deal for them.
The employers' body, IBEC, has also called on teachers to return to work. It said any grievances they had should be resolved within the Programme for Prosperity and Fairness (PPF).
The Association of Secondary Teachers, Ireland (ASTI) has become increasingly isolated in recent days. Government, other unions, parents and employers have become increasingly critical of its action for a 30 per cent pay claim.
Yesterday its 16,000 members withdrew from supervision duties, resulting in classes in more than 600 schools being cancelled. Similar action takes place today and tomorrow.
The ASTI standing committee will meet tomorrow to review strategy. Last night it again ruled out participating in the benchmarking review body.
The union hopes to mobilise 5,000 teachers for a national protest next Tuesday. The turnout will give an indication of the strength of feeling among the grassroots membership.
The National Parents Council (Post-Primary) has been reluctant to strongly condemn the union's action. However, constituent groups within this umbrella body have now broken ranks and criticised the ASTI.
One of these, the Congress of Catholic Secondary Schools Parents Associations (CSPA), said it was considering marching next Tuesday when teachers plan to hold their rally in Dublin.
CSPA spokeswoman Ms Barbara Johnston again called on parents to send their children to school this morning even though classes will be cancelled.
However, this was described as unwise by the National Parents Council's (Post-Primary) spokesman, Mr John Whyte. It has advised parents not to send children to school.
Ms Johnston said her organisation was considering a march because it looked like the only action left to parents who were concerned about their children's education.
Meanwhile, Dr Woods, in a hard-hitting Dail statement, said the ASTI action was felt "most acutely by students in examination classes".
"Even more disappointing is the renewal of the threat to the examination process. The threat by the ASTI that they would attempt to disrupt the examinations system is almost unthinkable," he said.
The union has refused to rule out withdrawing from the State exams in February.
ASTI general secretary Mr Charlie Lennon said Dr Woods should provide a framework for talks between the ASTI and the Government. "Such a framework should ensure that the issues raised in the ASTI dispute are resolved."