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Coming in at No. 15: Emma Watson

Smart stats:
• She attended the renowned Dragon School in Oxford and then went on to study at Headington School.
• She achieved ten A grades in her GCSEs while filming for the "Harry Potter" movies. Pretty impressive.
• She is currently enrolled at Brown University (although there are rumors that she might take a small break to focus on her acting career).

If that's not enough to convince you, Emma Watson plays the brainy Hermione Granger in the "Harry Potter" series. 'Nuff said.