Basis Scottsdale, a charter school in Arizona, is the best public high school in America.

It dates back nearly 20 years, to when two economists struggled to find a school that could provide a rigorous education for their daughter. They started a charter school in Tucson with the belief that the goal of a great education should be to provide students with limitless opportunities. A second high school opened in the affluent suburb of Scottsdale in 2003.

In 2017, four out of the top five public schools — according to a ranking from US News and World Report — are all managed by Basis Educational Group LLC, a for-profit company.

Charter schools are public schools that are privately run. Their supporters see them as providing a leg up for underserved students who lack access to a personalized education, while critics say they snatch away limited resources from other public schools.

Polarizing as they may be, charter schools have a track record of success. Business Insider spent the day at Basis Scottsdale to see what makes it the best in the nation.

Read the full article by Melia Robinson about public schools from Business Insider