JUST MAKE TEACHING AN OPTION IN A NATIONAL SERVICE PROGRAM...:

Hiring hundreds of thousands of additional teachers won't improve student achievement. It will bankrupt state and local governments, whose finances are already buckling under bloated payrolls with overly generous and grossly underfunded pension and health benefits.

For decades we have tried to boost academic outcomes by hiring more teachers, and we have essentially nothing to show for it. In 1970, public schools employed 2.06 million teachers, or one for every 22.3 students, according to the U.S. Department of Education's Digest of Education Statistics. In 2012, we have 3.27 million teachers, one for every 15.2 students.

Yet math and reading scores for 17-year-olds have remained virtually unchanged since 1970, according to the U.S. Department of Education's National Assessment of Educational Progress. The federal estimate of high-school graduation rates also shows no progress (with about 75% of students completing high school then and now). Unless the next teacher-hiring binge produces something that the last several couldn't, there is no reason to expect it to contribute to student outcomes.

Most people expect that more individualized attention from teachers should help students learn. The problem is that expanding the number of hires means dipping deeper into the potential teacher labor pool. That means additional teachers are likely to be weaker than current ones.

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