Which country has the best education system? Since 2000, every three years, 15-year-olds in dozens of countries have taken the Program for International Student Assessment — a standardized test of math, reading and science skills. On the inaugural test, which focused on reading, the top country came as a big surprise: tiny Finland. Finnish students claimed victory again in 2003 (when the focus was on math) and 2006 (when it was on science), all while spending about the same time on homework per week as the typical teenager in Shanghai does in a single day.
Just over a decade later, Europe had a new champion. Here, too, it wasn’t one of the usual suspects — not a big, wealthy country like Germany or Britain but the small underdog nation of Estonia. Since that time, experts have been searching for the secrets behind these countries’ educational excellence. They recently found one right here in the United States.
In North Carolina, economists examined data on several million elementary school students. They discovered a common pattern across about 7,000 classrooms that achieved significant gains in math and reading performance.
Those students didn’t have better teachers. They just happened to have the same teacher at least twice in different grades. A separate team of economists replicated the study with nearly a million elementary and middle schoolers in Indiana — and found the same results.
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