Testing the tests.
When I see massive teacher resistance to such tests (as we’ve had recently here in NJ), I suspect they fear the scales will fall from parents’ eyes regarding the “education” their children are receiving. They’ve been sending home glowing report cards for decades, and the students don’t know very much. My children’s classes have received “extra credit” for bringing cans in for food drives, attending “multicultural night” (for English extra credit?), etc.; if these tests expose the lies, the sooner the better.