Gaziano had himself quite the career while playing at Xaverian Brothers High School. The Scituate, Massachusetts, native helped lead his team to a 12-0 State Championship season while being named the 2014 Massachusetts Player of the Year after recording 53 tackles, 21 tackles for loss, and 16 sacks. He was also named the number one prospect in the state and was labeled a three-star prospect by Rivals.com.
After captaining the East team in the Semper Fidelis High School All-American Game, Gaziano decided to commit Northwestern over the home state school Boston College, as well as Syracuse and Rutgers.