2009-10: Terrance Amorosa skated for the Lac St-Louis Royals Espoir midget AA team in suburban Montreal. He scored 1 goal with 5 assists in 23 games.
2010-11: Amorosa played for the West Island Royals midget AA team. He scored 5 goals with 15 assists and had 6 penalty minutes in 31 games.
2011-12: Amorosa attended the Holderness School in New Hampshire. He skated in 29 games as a sophomore and had 6 goals with 9 assists. Holderness reached the championship game of the New England Prep School Ice Hockey Association Small School tournament, falling 3-2 in overtime to Kimball Union.
2012-13: Amorosa skated in 29 games as a junior in his second season at Holderness. He scored 12 goals with 14 assists. Holderness reached the semifinals of the NEPSIHA Small School tournament, falling to top seed Kents Hill, 4-1. Amorosa, not among the 210 North American skaters in Central Scouting's final rankings, was selected by Philadelphia in the fifth round (132nd overall) of the 2013 NHL Draft.