Not in all states. In my state (North Carolina), teachers participate in the public employees retirement/pension fund. However, public employees are prohibited

Not in all states. In my state (North Carolina), teachers participate in the public employees retirement/pension fund. However, public employees are prohibited by law from joining/forming a union. Yes, the get "summers off", but there are also mandatory continuing education requirements that must be completed, so they're still working (unpaid) during those two months. Teachers also cannot request a vacation day. If you need to call in sick, you're responsible for securing a substitute (school provides the list of approved people, better start calling them frantically).