Maybe education is good enough already

When it comes to improving schools, the only metric that's ever discussed is getting more out of them. We talk about improving test scores, we talk about increasing graduation rates, and we talk about sending more kids to college. However, the true measure of how good schools are is not what we get out them but how much we get out of them compared with what we put into them. Benefit/cost ratio. Net benefit. Whatever.

The Law of Diminishing returns, one of the few universally recognized laws in economics, says that the amount of a good you can produce decreases as you increase the inputs. The first acre of farmland will be the one with the most fertile soil, close to the railway or river for shipping, in the spot with the best climate. The two-billionth acre will be in Arizona, requiring irrigation and producing barely enough to justify using it at all. Education is like that, too.

The first dollar we spend educating a student teaches him to read. That's pretty important. The fifteen-thousandth dollar lets him watch Molly Ringwald movies in forth period health class. I submit that the last dollar is not as valuable as the first. In fact, I suggest that the last dollar spent does not provide even one dollar's worth of benefit. It is wasted, and would be better not spent on education at all.

What's the point? Well, when we evaluate schools, we should consider not only the gains the students make, but the gains they make per dollar spent. Maybe the best way to improve schools is to cut funding.