You need to be at a public school and in a union to make the bucks. Private school teachers make very little (at least parochial ones). Ironically, 9 times out of 10 you get a better education at a private school.
The DISD stands for the Dallas Independent School District; they ARE public schools. Nobody said anything to me about joining a union when they offered me the job.
By the way, I disagree that you get a better education at private schools. We had some kids transfer in to my high school from private schools and god, were they ever stupid.