The reason the battle in Wisconsin is so bitter is that the Wisconsin Republicans are doing what Reagan attempted to do and failed to do: Defund the left.
Previously schools were required to buy health insurance through the teachers union. Being free to shop around for health insurance appears to save over half a million dollars per school The dissenting opinion, The Stratasphere, Public School Spending
That is over a half a million dollars a year of taxpayer funded left wing activism in every school district, some of which appears to have been spent on rentamobs.