Updated 2 hours 51 minutes ago A discussion among students at Oberlin High School in Oberlin, La., about a mathematical symbol led to a police investigation and a search of one of the student’s homes, according to the Allen Parish Sheriff’s Office. On the afternoon of Feb. 20, detectives investigated a report of terroristic threats at the school, where they learned that a student had been completing a math problem that required drawing the square-root sign. Students in the group began commenting that the symbol, which represents a number that when multiplied by itself equals another number, looked like a...