It is frequently said that educating children is not like making widgets because every child is different. As a result, the end quality of the widget is highly dependent upon the material with which you start. Some of the starting material is simply defective and will never produce a suitable widget.
There is, of course, a grain of truth in this argument. But, based on NAEP, about two thirds of our educational widgets roll of the assembly line broken. Educators would have us believe that all the broken widgets are due to defective starting material because their underlying assumption is that they presently are doing the best that they can.
I think there is sufficient research out there that convincingly shows that no more than about 10% of the starting material is fatally defective. This means that about 85% of the broken widgets produced by our education system are not the result of defective material, but rather the result of a broken manufacturing process (the instructional delivery system).
With these parameters in mind, let's analyze the starting material.
Sure, the material comes in differing qualities. Most of the material is average quality. Some is below average and some is of exceptional quality. As I've pointed out above, 90% of the material is capable of being crafted into an acceptable finished widget. But, some of the material will take a great deal of skill to fashion, while some of the material almost builds itself. The weakest material will always result in the vast majority of broken end products. And, the best material will have the fewest.
Let's use the story of the three little pigs to illustrate the point (as if I haven't tortured this metaphor enough already).
The Brick House
The pig with the bricks (the best material) doesn't have to build his house that carefully. It will easily stand up to the big bad wolf. Even with sloppy building, the brick house will often be the strongest and will produce the least number of houses unable to withstand the wolf.
The Wood House
The pig with the wood (average material) has to attend to more details in building his house and has to employ a good design or else it won't stand up to the wolf. Even with careful building, the wood house most likely will not be as strong as the the brick house. And, more of the wood houses will fail when the wolf comes.
The Straw House
The pig with the straw (the weakest material) has a very difficult job ahead of him. He has to build his house very carefully and has to monitor the process every step of the way. He has to use efficient and advanced building techniques to make sure the house is up in time before the wolf comes a knockin'. Any errors are potentially fatal, especially errors building the foundation. This pig has to get everything exactly right and work at an accelerated pace or he'll get eaten by the wolf.
Even with careful building, the straw house will most likely be weaker than the wood house. But the well built straw house can withstand the wolf when he comes. But, overall, the greatest number of failures will be straw houses.
In education today, the craftsmanship standard is average to sloppy. Most brick houses stand up, some of the wood ones do too, but almost none of the straw ones do.
And bear in mind that in most states the big bad wolf is emphysemic.