Gerald Bracey offers a wonderful example of why more students need to leave school with a much better understanding of the basics of statistics.

The longtime debunker of misinformation about American public education, turns his formidable analytical skills on our favorite system of smoke and mirrors to explain One Reason (Among Many) That No Child Left Behind Cannot Work.

The law effectively guarantees that we cannot obtain 100 percent proficiency because it requires that the tests that measure whether or not we are proficient be keyed to “challenging” standards. But challenging standards are those that, by definition, not everyone can meet. If everyone could, they wouldn’t be challenging.

There’s another problem: By defining achievement in terms of the percent attaining some level labeled “proficient,” we’re not actually measuring–we’re counting. We’re just setting up a barrier for people to jump over. We know how many got over it, but we have no idea how high the barrier really is or how high the kids actually jump.

Even assuming every child was capable of meeting “challenging” standards, a primary fact of educational life is that not all of them will get there at exactly the same time in their lives.

Just about any teacher or parent will tell you that kids learn at different rates. And no one-size-fits-all law can change that.

Here’s another fact of life. NCLB is basically another of those statistical juggling acts sold to people with no understanding of statistics.

nclb, bracey, statistics