I don't get the impression from your note that you understand the measurement system here.

Imagine that you teach sixth grade in a small school. For simplicity, we'll say that all the kids are always in the same class, year after year.

We look at all of your students' past history. We know that this student generally does well, no matter the teacher. We know that this student always does poorly, no matter the teacher. We know that many middle-of-the-road students do better some years and worse other years. We *also* discover that these middle-of-the-road students tend to do better or worse at the same time. That is, none of them did well with Mr X for second grade, but nearly all of them suddenly improved with Ms Y for fourth grade. We conclude that Mr X is not a good second grade teacher. We conclude that Ms Y is a good fourth grade teacher. They had Ms Z for fifth grade, which seemed to be a pretty normal teacher: no lost ground, but no unexpected gains.

Then we look at your performance in light of the individual students' past record. Did the "great" student continue doing well? Yes, but it probably had nothing to do with you. Did the "poor" student continue faiiling? Yes, but it probably had nothing to do with you. You get neither credit nor blame for these cases.

How about the kids in the middle? Did they do well? If they actually lost ground, or learned only a tiny amount of the required work, then you are a bad teacher. You might be the kind of bad teacher who can be improved with a different situation, different training, or different subject area, but your kids suffered from your teaching problems. You might also be the kind of bad teacher who can't be fixed, and the only solution there is to find a new career for you.

If, in the much more likely case, your students did about what we'd expect for sixth graders, then you're a "good enough" teacher. You should be hired again, and encouraged to keep up the "good enough" work, and given whatever support and training is available to make you into a fantastic teacher.

If they did better than expected, then you're a better-than-expected teacher and should be rewarded for your excellent performance.

It really is that simple.