In recent months, I've written in these pages about a "higher education bubble" - the notion that America is spending more than it can afford on higher education, driven by the kind of cheap credit (and mass infatuation) that fueled the housing bubble.

Nothing has happened to make me doubt that, and in fact, we're beginning to see universities (like the University of the South at Sewanee, and several major law schools) actually cutting tuition, or freezing it, in the face of newfound customer price-resistance.

But, while the higher education bubble begins to deflate, I think we're also starting to see the deflation of what might be called a "lower education bubble" - that is, the constant flow of more and more money into K-12 education without any significant degree of buyer resistance, in spite of the often low quality of the education it purchases.

The leading case in point here is the battle over public-employee unions in Wisconsin and elsewhere. And it bodes poorly for the state of lower education.

Wisconsin spends a lot of money on education, and its teachers are well-paid. The average total compensation for a teacher in the Milwaukee public schools is over $100,000 per year.

In fact, Wisconsin spends more money per pupil than any other state in the Midwest. Nonetheless, two-thirds of Wisconsin eighth-graders can't read proficiently.

But it gets worse: "The test also showed that the reading abilities of Wisconsin public-school eighth graders had not improved at all between 1998 and 2009, despite a significant inflation-adjusted increase in the amount of money Wisconsin public schools spent per pupil each year. . . . from 1998 to 2008, Wisconsin public schools increased their per pupil spending by $4,245 in real terms yet did not add a single point to the reading scores of their eighth graders and still could lift only one-third of their eighth graders to at least a 'proficient' level in reading."

So it's lots of pay but not much in the way of performance. And in this, alas, Wisconsin's situation is typical of public education at the K-12 level around the country. (In fact, one of the reasons given for the increase in higher-education costs is the need to provide remedial education to many high school graduates, who never managed to learn the things they were supposed to have learned before they arrived at college. As an explanation for high college costs it's shaky, but the phenomenon itself is beyond dispute).

So at the K-12 level, we've got an educational system that in many fundamental ways hasn't changed in 100 years - except, of course, by becoming much less rigorous - but that nonetheless has become vastly more expensive without producing significantly better results.

In the past, when problems with education were raised, the solution was always to spend more money. But as economist Herbert Stein once noted, something that can't go on forever, won't. Steady increases in per-pupil spending without any commensurate increase in learning can't go on forever. So they won't. And as state after state faces near-bankruptcy (or, in some cases, actual bankruptcy), we've pretty much hit that point now.

So what does that mean? Well, in the short term, it means showdowns like the one in Wisconsin, where the folks who received those big increases in the past now rage against the drying-up of the government teat.

Getting rid of teachers' unions and overgenerous, underfunded public pensions is something states will have to do to remain solvent. But that's just the short term. Over the longer term - which means, really, the next three to five years at most - straitened circumstances and the need for better education will require more significant change.

When our public education system was created in the 19th century, its goal, quite explicitly, was to produce obedient and orderly factory workers to fill the new jobs being created by the industrial revolution. Those jobs are mostly gone, now, and the needs of the 21st century are not the needs of the 19th.

Perhaps there's still a role for teaching children to sit up straight and form lines, but perhaps not. Certainly the rapidly increasing willingness of parents to try homeschooling, charter schools, online school, and other alternative approaches suggests that a lot of people are unhappy with the status quo.

Like striking steelworkers in the 1970s, today's teachers' immediate unhappiness may come from reductions in benefits. But their bigger problem is an industry that hasn't kept up with the times, and isn't producing the value it once did. Until that changes, we're likely to see deflation of the lower education bubble as well as the higher.

Examiner Sunday Reflection contributor Glenn Harlan Reynolds is founder and editor of Instapundit.com and a law professor at the University of Tennessee in Knoxville.