By Dr. Marciene Mattleman

PHILADELPHIA (CBS) – In 2006, Salman Khan, a hedge fund manager, started tutoring family members, developing and posting short math instructional videos on YouTube. In 2008 he established a non-profit, quitting his job and creating the Khan Academy.

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With all but a handful of states adopting the Common Core standards now, educators nationwide are searching for relevant instructional materials and Khan Academy has linked thousands of interactive online math exercises to the math content for K-12 teachers at no cost.

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The approach has been criticized for giving strategies for doing problems, rather than dealing with the concepts. On the positive side, Khan Academy has been important for teachers who need to individualize instruction at varied levels of proficiency.

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An article in Education Week talks about the role of this adaptive technology, sure to have competitors, but Salman Khan, who is also partnering with the College Board on the SAT, hopes his informal approach doesn’t “lose its charm.”