Teachers' union the ASTI has said news that a school is sending students home early as a result of budget cuts demonstrates the agonising choices some schools have had to make recently.
RTÉ News has spoken to one secondary school that said it is being forced to send first year and second year students home early four and two days a week respectively due to staffing cuts.
A second school said it was timetabling study classes for students because it did not have enough teachers.
Both of these steps are against Department of Education regulations, which stipulate a set number of hours of teaching for students.
The schools said that due to the needs of their students, they had decided they could not cut guidance counselling hours or increase class size to compensate for the cuts.
These are steps that other schools have taken.
Both schools spoke to RTÉ on the condition that they would not be identified.
The ASTI said second-level schools were in a catch-22 situation with no choice but to make decisions that would impact negatively on the education of their students.
The union said the news affirmed its warning to Minister for Education Ruairi Quinn that further cuts would push schools to breaking point.
Other schools have amalgamated higher and ordinary level classes to cope with the cuts.
The Department and the Minister for Education have said they are surprised and concerned to hear reports that some schools have chosen to deprive students of tuition time.
The department said that it is "acknowledged that schools face challenges in managing their allocations due to the extremely challenging budgetary position that has meant reductions in teacher allocations by the last and current governments".
It added that the "integrity of the class time for students must be protected".