Bryce Marcus is a fifth-grader at the KIPP Infinity School in the West Harlem neighborhood of New York City. His curriculum includes emotional development training that teaches him to replace negative thinking with more realistic and flexible thinking. Allison Aubrey/NPR hide caption

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Sam Kass, the assistant White House chef, picks spinach from the garden. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

A jogger runs near downtown Houston. Recent studies show that running doesn't increase the risk of arthritis, and some runner's actually have healthier joints. David J. Phillip/AP hide caption

itoggle caption David J. Phillip/AP

Being in the right place at the right time, like living in the same college dorm, is a strong predictor of friendship. hide caption

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tc John Poole/NPR hide caption

itoggle caption John Poole/NPR
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