Here, drawn from my new e-book, Launching the Innovation Renaissance (published by TED) is part of a section on college education. (See also the op-ed in IBD)

Educated people have higher wages and lower unemployment rates than the less educated so why are college students at Occupy Wall Street protests around the country demanding forgiveness for crushing student debt? The sluggish economy is tough on everyone but the students are also learning a hard lesson, going to college is not enough. You also have to study the right subjects. And American students are not studying the fields with the greatest economic potential.

Over the past 25 years the total number of students in college has increased by about 50 percent. But the number of students graduating with degrees in science, technology, engineering and math (the so-called STEM fields) has remained more or less constant. Moreover, many of today’s STEM graduates are foreign born and are taking their knowledge and skills back to their native countries.

Consider computer technology. In 2009 the U.S. graduated 37,994 students with bachelor’s degrees in computer and information science. This is not bad, but we graduated more students with computer science degrees 25 years ago! The story is the same in other technology fields such as chemical engineering, math and statistics. Few fields have changed as much in recent years as microbiology, but in 2009 we graduated just 2,480 students with bachelor’s degrees in microbiology — about the same number as 25 years ago. Who will solve the problem of antibiotic resistance?

If students aren’t studying science, technology, engineering and math, what are they studying?

In 2009 the U.S. graduated 89,140 students in the visual and performing arts, more than in computer science, math and chemical engineering combined and more than double the number of visual and performing arts graduates in 1985.

The chart at right shows the number of bachelor’s degrees in various fields today and 25 years ago. STEM fields are flat (declining for natives) while the visual and performing arts, psychology, and communication and journalism (!) are way up.

There is nothing wrong with the arts, psychology and journalism, but graduates in these fields have lower wages and are less likely to find work in their fields than graduates in science and math. Moreover, more than half of all humanities graduates end up in jobs that don’t require college degrees and these graduates don’t get a big college bonus.

Most importantly, graduates in the arts, psychology and journalism are less likely to create the kinds of innovations that drive economic growth. Economic growth is not a magic totem to which all else must bow, but it is one of the main reasons we subsidize higher education.

The potential wage gains for college graduates go to the graduates — that’s reason enough for students to pursue a college education. We add subsidies to the mix, however, because we believe that education has positive spillover benefits that flow to society. One of the biggest of these benefits is the increase in innovation that highly educated workers theoretically bring to the economy.

As a result, an argument can be made for subsidizing students in fields with potentially large spillovers, such as microbiology, chemical engineering, nuclear physics and computer science. There is little justification for subsidizing sociology, dance and English majors.

College has been oversold. It has been oversold to students who end up dropping out or graduating with degrees that don’t help them very much in the job market. It also has been oversold to the taxpayers, who foot the bill for these subsidies.