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Children run across an interactive exhibit at the new National Museum of Mathematics in New York, Monday, Dec. 17, 2012. The museum is aimed at kids aged 8 to 13, and curators have given the place a playground feel. The 40 exhibits include a "wall of fire" made up of laser lights that teaches kids about geometry and a square-wheeled tricycle that still manages to produce a smooth ride thanks to a wavy track.
((AP Photo/Seth Wenig))