March 14 is Pi Day, and to commemorate the mathematical constant, the Children&#39;s Museum of Houston closed off a side street in the Museum District and invited 100 children and adults to participate in a shaving cream fight. The battle started precisely at 1:59pm, cleverly paying homage to pi by using its first few numbers, 3.14159. <span class=meta>(KTRK Photo&#47; Mena El-Sharkawi)</span>
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