By Dr. Marciene Mattleman

PHILADELPHIA (CBS) – Cambridge University has educated students for more than 800 years and now its pre-collegiate courses, focusing on critical thinking and in-depth analysis, are spreading internationally.

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Its academic program is used in 9,000 schools in 160 countries with students 8-19-years-old and growth to 230 mostly public schools in 27 states in the US has been rapid.

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The approach of Cambridge is rigorous and deep. In history, rather than memorize dates and take multiple choice tests, research is done using primary sources, developing arguments and synthesizing in a writing intensive format. Math and science are often integrated and traditional basic skills are taught at the elementary and middle school level in addition to 70 courses including biology and economics.

Schools differ in how they use the program and although its name is Cambridge International Exams, students can take one class or take exams and gain credits for a certificate.

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Read more in Education Week.