Henry Petroski, author of To Engineer is Human, tells how he introduces the concept of structural fatigue to engineering students.
I bring a box of paper clips to class. In front of the class I open one of the paper clips flat and then bend it back and forth until it breaks in two. That, I tell the class, is failure by fatigue, and I point out that the number of back and forth cycles it takes to break the paper clip depends not only on how strong the paper clip is but also on how severely I bend it...Having said this, I pass out a half dozen or so clips to each of the students and ask them to bend their clips to breaking...
Dr. Petroski records the results of their "low-budget experiment" on the board.
Invariably the results fall clearly under a bell-shaped normal curve that indicates the statistical distribution of the results, and I elicit from the students the explanations as to why not all the paper clips broke with the same number of bendings. Everyone usually agrees on two main reasons: not all paper clips are equally strong, and not every student bends his clips in exactly the same way. Thus the students recognize the fact that failure by fatigue is not a precisely predictable event.
I said it was a parable, and like most parables, it has a moral. To wit: high-quality teaching requires neither advanced technology nor lots of money. I have examined school budgets, and always, there is plenty of room for significant savings at no loss of instructional effectiveness, but for turf wars.
I will admit that I have not yet examined budgets of schools in other than middle class or rural schools, so it is possible my observations will not hold for all budgets. Nevertheless, many budgets have a problem with priorities. There is something wrong when a school board will deny raises for three administrative assistants making about $20,000 per year each, and then turns around and approves a 5 percent raise for the superintendent making $100,000 per year. I saw it happen; I was at the school board meetings.
Meanwhile, the library just had to have a new computer lab with all the bells and whistles, a lab (like most school technology) is so rarely used that it is hard to justify the expense. Down the road, the local intentionally low-tech Waldorf School was producing better results with a lot less money, as was true of most of the private schools, even when controlling for the higher public school salaries. People first, then things.