· Just one in 10 of the students surveyed could answer the toughest financial-literacy questions on the 2012 survey, such as the impact of income-tax brackets on people’s finances.

· On average, teens from higher-socioeconomic backgrounds scored a full 41 points higher on the financial-literacy section than poorer kids. That holds true across countries, meaning that thousands of poor kids worldwide begin their financial lives with less knowledge and at a disadvantage.

· Similarly, huge gaps exist in teens who say they hold bank accounts—an easy, important way to accumulate savings. In Australia, Belgium, Estonia, France, New Zealand, and Slovenia, more than 70 percent of 15-year-old students reported that they has opened an account, whereas in Israel and Poland, fewer than 30 percent of students had.