The Educational Institute of Scotland (EIS) hit out after Glasgow City Council announced the measures as part of £70m budget cuts in the next two years.
The cuts include merging and relocating specialist schools for children with learning difficulties and reducing support for learning teachers to save £2.5m.
The councils also intends to replace teachers in nursery classes with child development officers, having one head across several nurseries and changing school timetables to save a further £5m. School maintenance will be scaled back to save £1.5m, after-hours clubs reduced for £100,000 and increasing the cost of a school let for £800,000.
Larry Flanagan, general secretary of the EIS, said: "The continuing removal of teachers from nursery establishments means that young children are being denied the access to a teacher that was a key pre-election commitment for the Scottish Government."
However, a council spokeswoman said: "The council's budgets are under intense pressure and the proposals are about protecting priority areas."