Many of our TSC signatories come from backgrounds in teaching, administration, on-the-ground education reform efforts, or they are parents who believe in the issue. But some supporters of ELT are drawn in by the threat that our public education system is preparing a generation of Americans that will be unable to compete in the 21st century. Today in the Huffington Post, Columbia professor and UN economist Howard Steven Friedman makes the economic case for expanded learning time.

One of my favorite aspects of Friedman’s argument is his insistence on the complexity of expanding learning time. No, tacking a few hours onto the day is not enough, but redesigning and expanding the school time is working – as is more high-quality learning time in school in South Korea and Japan.

Friedman has the data to back it up: “For the 14 wealthy countries studied in Measure of a Nation, the data show clearly that there is a correlation of about ninety percent between the number of days a child attends school and the PISA [international] exam scores.” Longer school years, he continues, “are one of the leading practices found in other countries that are excelling at primary and secondary education.”

It’s intuitive information, but a quick look at the PISA scores make it impossible to ignore. All of our students and teachers deserve an even playing field. If we want to form competitive 21st-century leaders, we need them to have an even playing field. Expanded learning time should be a part of the solution.

Charlotte is a summer intern for the Time to Succeed Coalition. She will be a rising junior at Yale University in the fall.