If we can just help parents overcome their fear of saying No to testing, their fear of what will happen if their school doesn’t make AYP, we can end this all now. Only 10% of parents and/or kids have to decline testing and it’s over. The 10% isn’t some mystical 100-monkeys number.
According to psychometricians, if the tests fail to test the same percentage each year, all the stats are invalid. That’s why there is extreme pressure on schools to test 100% and why there is the threat of failing if the percentage for the whole school OR for any measurable subgroup falls below 95%. In fact, for small rural schools, their scores are statistically meaningless anyway, but they still have to take the test, or else we could all sue under the equal protection clause.