Tenured positions, strong unions, pensions, benefits the average blue collared worker can dream of, and no accountability or pressures to ensure students make their marks. I can support raises once merit pay is instituted and they start doing something about the bad teachers, of which young me would say is the majority.
Tenured? We are talking kindergarten here. Also, are you seriously comparing an advanced-degree career to blue-collar workers?
How is it you'd institute a merit system? By the volume-of-students-per-hour, or what, exactly? The least complaining parents? Test scores that depend on parental involvement to be any good? How are disinterested or absentee parents or those parents who have it in for teachers accounted for in such a system?
The teachers union where I am is strong, but it doesn't preclude the administration from playing tricks similar to the exactly 39-hour "part time" employee. Specifically, the teachers get "fired" on the last day of the school year, and turn hired back in the fall, in some sort of adminstration-union rule avoiding shell game.