The TUI conference in Galway has been told that cutbacks in second chance learning opportunities for adults will have disastrous consequences.
The union says a decision to ban any increase in the number of students being allowed to take post leaving certificate courses is a hugely retrograde step that should be reversed immediately.
About 30,000 young adults avail of second chance courses each year but the Department of Education is now instructing all schools to limit or cap the numbers who can avail of these courses.
John McGowan, the union's education research officer, said the PLC courses were creating enormous opportunities for young adults, particularly in areas of serious disadvantage.
The courses open the door to third level qualifications or high quality jobs, he said, and the department's 'hostility' in allowing these schemes to go was inexplicable.
The Education Minister, Noel Dempsey, addressed the TUI conference in Galway this afternoon.