The U.S. public education system is trying any number of techniques—from charter schools to presidential initiatives to oil-company-run teacher academies—to catch up to countries like Finland and South Korea in math and science education. But policymakers seem to be overlooking one simple solution: requiring math and science teachers to progress further up the educational ladder before they teach those subjects to kids.

The map above shows the minimum level of education each country requires teachers to obtain before working at the upper-secondary level. The map, based on data collected by Jody Heymann and the World Policy Analysis Center and subsequently published in Children’s Chances: How Countries Can Move from Surviving to Thriving, illustrates that the United States lags behind most other countries in its requirements.

Many U.S. school systems defer to teachers with higher degrees when they hire faculty, and teachers are required to have some kind of state certification along with a bachelor’s degree. However, the precise certification requirements vary, depending on how a teacher enters the profession and what state they teach in. The traditional route to becoming a teacher in the United States usually involves a bachelor’s or master’s degree in education along with a standardized test and other state-specific requirements. But most states have some form of an alternative route, usually involving a bachelor’s degree and completion of an alternate certification program while a person simultaneously teaches full-time. There is no federal mandate for teacher education requirements, according to the World Policy Analysis Center. The federal Improving Teacher Quality State Grants program rewards states with funds when they meet the “highly qualified teacher” requirement set forth in the No Child Left Behind Act.

Read it at Slate.