Middle School Math Pre Tests

Any math teachers here use pre tests? PaulB, are you around? I think your school required you to use them, but I can't find the thread where you talked about how it was (not) working.

I am wondering what the stated purpose is of the pre tests.

I can see someone offering the following explanation:

A pre test is a useful way to determine the current knowledge level/ability/readiness for the material about to be taught.

But then what? Once you determine that, how is that knowledge to be used? Are teachers who are required to pretest allowed to change their content? Slow down? Reteach? Repeat prior material? If an individual student were to ace the pre test would they be exempted?

Is this to help the teacher know where the "differentiated" in the classroom are in skill set (as if he didn't know already?)?

I heard some anecdotes about the use of pre tests in middle school math here, but didn't understand the constraints under which the teacher performed. In that teacher's case, implementation issues were a problem.

The main issue was that the teacher sent the pre tests home. At least some of the students and parents didn't understand that this was a pre test, and thought their children were performing poorly. The students too seemed to internalize that doing badly on the pre test meant they were bad at math. No protestations to the contrary by the teacher mattered. (proposed solution: grade but do not return pre tests to children or parents, though unclear if that was within the teacher's purview to control.)

Even without the pre test being sent home, the student internalization seems a real issue. Constantly giving tests to kids where they know they can't do the work seems to be the definition of negative reinforcement.

To me, pre tests seem valuable only to very mature students who can use them to tailor their -own- preparation for the course material. To me, this smacks of the case of those twin ideas "kids need to be prepared for college so they must act like college students now" and "experts do this so we need to teach the novices to do it the same way". That is, someone saw that college professors use pre tests on their students, so middle school teachers should do the same.

One thing seems clear: if you didn't have a spiral curriculum, then with awfully few exceptions, the prior ending unit test would BE a pre test, voila!

UPDATE: Mark Roulo's comment made clear that my post was unclear. I meant giving pre tests at the beginning of every chapter/unit/thread in the math class, not just at the beginning and end of a semester or year. So students are getting a "pre test" every 2-3 weeks, and say, the day after the get an end test on the material they've just been shown, but the pre test is on material they have not yet seen, or supposedly on the prereqs for the material they are about to see.