The trouble with TVAAS

Recently the state has released to teachers and administrators the infamous TVAAS scores. TVAAS (Tennessee Value-Added Assessment System) is supposed to be an "objective and more precise way to measure student progress and the value schools and systems add to students' educational experiences". You can read more about TVAAS here, but let me shed some light on my perspective on TVAAS.

First of all, let me break down the TVAAS mission statement as it were. An "objective and more precise way to measure student progress and the value schools and systems add to students' educational experiences".... yeah, sure, ok. Because test scores like SAT-10, TCAP, and EoCs can measure all of that. Plain and simple there is no "objective" way to measure the value that teachers add to students' educational experiences. Can you graph when students become interested in learning? Can data show you which teachers make kids love to come to school? Can a test show the teachers who work their tails off for kids who come in 100% unprepared? To me, those are things that we should value. Those are the things that teachers add to students' educational experiences. Those are the things that test scores can't show us.

But, enough of that. I want to show you my overall composite paper from the TVAAS system. So, I'm any given teacher across the state of Tennessee who tried to log on and see my TVAAS scores. Let me tell you-- they don't make it easy. I consider myself quite computer literate and it took me a looong time to find what I was looking for and then to try and understand it. Anyway,  when I finally find my overall score sheet, here's what it looks like (minus the blacked out parts):

As you can see in tiny letters at the bottom, teachers are determined by their student's growth on test scores if they are a Level 1-5, with 5 being the best. The top part of the form is specific to me, while the bottom part shows state-wide information. But wait-- let's take a closer look at the bottom part, shall we?

Upon further inspection, the breakdown of the state distribution of teachers looks like this:
Level 5: 11,291
Level 4: 3,553
Level 3: 8,028
Level 2: 3,054
Level 1: 5,497

So what the state is saying is that out of 31,423 teachers in the state of Tennessee, roughly 17% are a Level 1, 10% are a Level 2, 25% are a Level 3, 11% are a Level 4 and a whopping 36% are a Level 5. The state's data shows that over a third of Tennessee teachers are those "whose students are making more progress that the state growth standard/ state average".

I'm not a statistics person... but I know enough to understand that you can make the stats say almost anything you want. So it's puzzling to me that 36% of teachers have students that are making more progress than the average. What ever happened to the bell curve? If we tried to make a bell curve out of this data it would look like this:

 Like I said, I'm not master of statistics, but it seems unreasonable to me to say that most teachers were a Level 5 based off of their scores for the past 3 years. If that many teachers were doing that great of a job, wouldn't we find ourselves in a much better spot in education? And, how can this trend continue over the next 3, 5, 10, 15 years? How can so many kids show so much growth every year that their teachers continue to be Level 5s?

This gives too little credit to the work teachers are doing. I know I was ranked too high, and I know that others in my building were ranked too low... all depending on what kids happened to get into their classroom and how those kids happened to perform on one state issued test. The bottom line for me is that you CANNOT objectively measure how effective I am. Last year, there was a girl in my class who will never be at the top of her class, and even if I didn't teach her one academic thing, I'd like to think I taught her that reading was fun, that people (including me) loved her, and that life was good. There's no objective test that can show that sort of human growth.

... P.S. A few days later the State sent out another email that effectively said "Oops, we may have miscalculated your score and let you see them prematurely... you may in fact have a very different score if you only teacher one subject...". Way to go to State.