There’s been much interest in the blogosphere recently over spiraling college costs. Niraj Chokshi kicked things off at the Atlantic, and the discussion was picked up by Andrew Sullivan and Ezra Klein, among others.

We’ll be hosting a debate on the causes of and solutions to this problem at Cato on the 6th of October, but in the meantime, it’s worth noting what the blogosphere has thus far overlooked: the epic productivity collapse in k-12 schooling over the past 40 years.

As I noted in Investors’ Business Daily last month, k-12 spending has risen by a factor of 2.3 since 1969, while achievement at the end of high-school is flat. The scary details can be found here.

If public school productivity had merely stayed where it was in 1970, instead of collapsing as it did, Americans would enjoy a permanent $300+ billion annual tax cut.

State-run schooling has become so profligate and inefficient, in fact, that one recent study finds higher public school spending is associated with LOWER subsequent economic growth.

Oh, and regarding the education vs. health care debate that started all this: k-12 productivity trends seem worse than those in health care.