PHOENIX -- Two suburban Phoenix schools aced a test and earned recognition as among the top systems in the world.
Basis Scottsdale and Chandler took the Organisation for Economic Co-operation and Development Test for Schools, an international assessment-and-comparison tool, in the spring.
Both charter schools performed exceptionally well in reading, math and science, besting schools from Shanghai, China. That school system produced the highest test scores in 2012 and has been the model for success for the test.
The test has been given at 65 schools around the world to 15-year-olds since 2009.
"We ask in class critical-thinking questions, things most schools don't," Stephanie Terrell said. Terrell heads the Chandler campus.
The Scottsdale school's reading score of 625 put it in the top 1 percent. Chandler scored 594 and Shanghai 556.
In math, Scottsdale racked up a 636 and Chandler 612. Scottsdale also breezed in science with 616. Chandler scored 585.
Basis schools have made appearances on U.S. News and World Report's list of best high schools in the country. KTAR's Cooper Rummell contributed to this article.