The main reason merit pay for teachers is a bad idea is that it provides absolutely zero consideration for parental irresponsibility. Thirty years ago, parents were expected to help children with homework, add discipline to correct misbehavior, and generally supported teachers and the school system with just punishments and consequences for misbehaviors like lying, cheating, stealing, talking back and disrespecting authority. Today, as I stated before, parent’s have said to my wife, a teacher, that they shouldn’t have to do homework with their children because “that’s your job,” meaning “the teacher’s.” With no reinforcement at home, no practice, not discipline, how can you even hope to measure a teacher’s performance?