In the U.S., your SAT score is hugely important. But what does it really measure?

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The SAT college extrance exam is a gatekeeper of opportunity. But this wasn't always the case.

Here are some sources I found useful when reporting out this piece:

* The Big Test is a well known book written by Nicholas Lemann, but a few years before he published this in 1999, he wrote this piece for The Atlantic: https://www.theatlantic.com/magazine/...

* Here's the story behind the SAT overhaul: https://www.nytimes.com/2014/03/09/ma...

* This research paper, from Raj Chetty and colleagues, looks at the role of colleges in intergenerational mobility: https://www.nber.org/papers/w23618

* The SAT helps predict first-year GPA to an extent — but not for all students. We didn't include this in our video, but this piece covers the research that shows the SAT isn't predictive for a huge portion of students: https://www.insidehighered.com/news/2...

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