Here's Why U.S. Students Test Poorly

June 25, 2013— -- The United States spends more money on its students per year than any other developed nation, according to a new study from the Organisation for Economic Co-operation and Development.

But American kids can't keep up with children from other countries on international tests.

What gives?

A few things.

1. Teacher salaries We don't pay our teachers very much. While they do okay in terms of straight salary compared to other nations, they haven't seen the same raises that other countries pass out. Teachers in other countries make about 82 percent of what their similarly educated peers earn. That figure drops to 66 percent in the U.S.

Teacher salaries have a huge impact when it comes to attracting good instructors. The innovative, smart, highly skilled people you want teaching your kids aren't exactly in love with the idea of making $38,000 per year (the average for first-year high school teachers) when they could go somewhere else and earn more while doing less.

2. Public spending The U.S. spends about $15,171 per student and more than seven percent of its GDP on education. The average for other countries is about six percent. Not all of that spending is public, though. Public investment in education went up among other developed countries but actually dropped slightly in the U.S.

Parents and private sources funded about 30 cents of each dollar spent per U.S. student in 2010. Other developed countries have more robust public spending, picking up about 84 cents of every dollar spent per student.

The amount of spending left to parents and foundations in the U.S. can lead to inequality. Wealthy parents are more able to contribute money to their kids' education, while kids in poor neighborhoods fall behind.

3. Post-high school spendingThe U.S. is also way behind when it comes to paying for education after high school. The U.S. covers just 36 cents per dollar on college and vocational programs. That's tiny compared to the 68 cents per dollar other countries spend.

Nearly half of all private spending on higher education in the U.S. comes from households. All those student loans you're worried about? Kids in Nordic countries don't have that problem because tuition is free.

While household spending on higher education has more than doubled in other developed countries over the past decade, public spending has also increased and countries have made a conscientious effort to keep quality high and access open.

4. Preschool attendance Other kids go to school earlier in life. Just half of U.S. kids see a classroom at the age of three. That number is closer to 70 percent in other developed countries. In Denmark, Finland and a handful of other countries, it's above 90 percent.

The OECD found in a separate study that 15-year-olds who had attended at least a year of preschool performed better on reading tests than kids who had not, even when socioeconomic factors were taken into account.

The U.S. spends more on preschool than other countries but money doesn't do any good unless kids are enrolled, and the U.S. lags on that measure.

5. College attendance The number of young people going to college in other countries is rising. While the U.S. ranks fifth in terms of how many adults have a post-high school degree, we drop to 12th place when you just look at young adults, 25-34.