Test Validity & Teacher Performance

On twitter, High high stakes corrupt performacne on tests, other indicators,” which is based on a blog post, Why do good policy makers use bad indicators?

Dr. Cuban’s points are fair, obvious, well known, and perhaps best said at thus:

  • No measure has perfect validity
  • The smaller the overlap between what you are measuring, what you are rewarding, and what you want to improve, the worse your reward system will be

In other words, nothing everyone doesn’t already know anyway. I talked at some length about the importance of validity in test design earlier, and I won’t repeat myself here. I will say though that we have to create good tests because teachers as a political class have abandoned the effort to educate young people.

In America, we have established a public monopoly over basic education at the same time we lobotomized the work force, hired below-average teachers, and made it harder to fire teachers by introducing “due process” rules. We all pay the price for this through more expensive mortgages, less jobs, and more outsourcing.

If we had a professional, capable, and effective teacher work-force, where bad teachers could be fired, we might not need to measure their output. But we don’t. We have a teacher work force with a lot of dead weight (and worse, actual cancers) that is failing our country.

If we were serious about creating a professional teacher labor force, we could treat teachers like professionals and evaluate them accordingly. We don’t, though. Thus the need for reliable, standard, valid, and practical tests to measure the achievement of students and the performance of teachers, schools, districts, and states.

For the time being, teachers oppose the introduction of tests, because this would mean that some teachers will lose their jobs. Teachers are in it for the money,  for the working conditions, and for the unaccountability. Unfortunately, as a political class, teachers are also lack empathy and understanding for other stakeholders. It is possible that the hard work to turn around teachers attitudes will succeed. Unless teachers begin caring about the success of their students, reform will come from above, which means establishing measures that are reliable, standard, valid, and practical, and using those to hire, promote, and dismiss teachers.