School board member here. Although I'm in a rural district very different than NYC. I did an analysis on this. ~1/3 or less goes to front line instruction in my district (the 95%.). Around 1/3 to special ed. And around 1/3 to overhead.
So you're not quite wrong in the back of the envelope, but the assumptions are way off. For example, the 1/3 special ed in my district is consumed not by high paid specialists but by huge numbers of aids coupled with outrageous costs for a few students with services that require private drivers (with cars!) plus all the special private services they need.
So you're not quite wrong in the back of the envelope, but the assumptions are way off. For example, the 1/3 special ed in my district is consumed not by high paid specialists but by huge numbers of aids coupled with outrageous costs for a few students with services that require private drivers (with cars!) plus all the special private services they need.