The Stanford-bound athlete led Boise to a fourth-place team finish at the 5A State Track and Field Championships, winning the 800, 1,500 and 3,200-meter championships.
Rigby's winning 800-meter dash time was a state record 1:50.80.
"Thomas Rigby had an amazing year for us in track and field," Boise High athletic director Tracy Leinen said in a press release provided by Gatorade.
"At the state meet, he just decided that he was going to step up give it his all. He did it with a lot of character and has become a leader in our school."
Rigby joins recent Gatorade Idaho Boys Track & Field Athletes of the Year Erik Harris (2011-12, Twin Falls High School), Dallas Burroughs (2010-11, Rocky Mountain High School), A.J. Boully (2009-10, Borah), Mitch Simmonds (2008-09, Cole Valley Christian), Eric Fitzpatrick (2007-08, Boise), and Taylor Farnsworth (2006-2007, Highland) among the state's list of former award winners.