Ninth graders at George Washington Carver Collegiate Academy learn to shake hands and greet each other during the first day of school in New Orleans. David Gilkey/NPR hide caption

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Dominic Rudakevych and Marilyn Fisher, 2014 champions of the National Marbles Championships in Wildwood, N.J., pose at the marbles rings in Middletown, Md. The two 13-year-olds train with the Frederick County Knucklers, a competitive marbles recreational program in Maryland. NPR/Sarah Tilotta hide caption

itoggle caption NPR/Sarah Tilotta