According to a 2010 study, “The U.S. recruits most teachers from the bottom two-thirds of college classes, and, for many schools in poor neighborhoods, from the bottom third.”

This is not surprising, according to Secretary of Education Arne Duncan, given that higher ranked college graduates can earn far more money in other fields:

McKinsey & Co. did a study (PDF) last year comparing the U.S. to other countries and found that America’s average current teacher salaries — starting around $35,000 and topping out at an average of $65,000 — were set far too low to attract and retain top talent. The McKinsey report found that starting teacher salaries have not kept pace with other fields. In 1970, beginning New York City lawyers earned $2,000 more than first-year teachers. Today, a starting lawyer there can earn three or four times as much as a beginning teacher. Money is never the sole reason that people enter teaching. But it is a reason why some talented people avoid teaching — or quit the profession when starting a family or buying a home. Other high-performing nations recruit teachers from the top third of college graduates. That must be our goal as well, and compensation is one critical factor. To encourage more top-caliber students to choose teaching, teachers should be paid a lot more, with starting salaries of $60,000 and potential earnings of $150,000.