The U.S. is home to some of the greatest colleges and universities in the world. But with the student debt load at more than $1 trillion and youth unemployment elevated, when assessing the value of a college education, that’s only one part of the story.

Former Secretary of Education William Bennett, author of Is College Worth It, sat down with The Daily Ticker on the sidelines of the Milken Institute's 2013 Global Conference to talk about whether college is worth it.

“We have about 21 million people in higher education, and about half the people who start four year colleges don’t finish,” Bennett tells The Daily Ticker. “Those who do finish, who graduated in 2011 - half were either unemployed or radically underemployed and in debt.”

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That average student loan balance for a 25-year-old is $20,326, according to the Federal Reserve of New York. Student debt is second largest source of U.S. household debt, after only mortgages.

Bennett assessed the “return on investment” for the 3500 colleges and universities in the country. He found that returns were positive for only 150 institutions. The top 10 schools ranked by Bennett as having the best "ROI" are below (for the full list he used, click here, and for the latest figures, click here):

1. Harvey Mudd College

2. California Institute of Technology

3. Massachusetts Institute of Technology (MIT)

4. Stanford University

5. Princeton University

6. Harvard University

7. Dartmouth College

8. Duke University

9. University of Pennsylvania

10. University of Notre Dame

He found college is “worth it” if you get into a top tier university like Stanford, or study an in-demand field like nuclear engineering at even a lower tier school.

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The problem, Bennett says, is people going to second-tier schools, majoring in less-marketable liberal arts fields, and taking on debt to do so.

Alternatives to a traditional four-year college include entering the workforce prior to college, joining the military, or going to a 2-year community college.

Bennet discovered, for example, graduates of Jefferson College of Health Science and Nursing in Virginia make more after two years than those from the prestigious University of Virginia in Charlottesville.

Also the rise in massive online offerings has lowered costs for taking a course to as little as $150.

As for what could turn around what some have called a student debt “bubble” in this country, Bennett has some ideas. They don’t involve changes to government policy or a massive overhaul of how colleges do business. They may involve tears and parents’ basements. You can watch the interview to find out.