The chess team from Edward R. Murrow High School in Brooklyn won its fourth consecutive national championship on Sunday, tying with a high school from Arizona. It was the second time in three years that Murrow and Catalina Foothills High School of Tucson were named co-winners of the National High School Championship. Each school earned 22 points in the tournament, which was held in Kansas City, Mo. Alex Lenderman, a Murrow senior who earned 6.5 points for his team, was named national scholastic chess champion, the tournament’s top individual honor.