Greig attended George Elliot Secondary School where she played basketball and ice hockey.
[1] During her sophomore season, she helped her team win the Detroit 2 Nations Cup Championship and was named the tournament's MVP.
During her junior year, she won the Canadian Sport School Hockey League Championship, scoring 25 goals and 38 assists for a league-high 63 points.
During her senior year, she recorded 20 goals and 42 assists in 25 games and won the Stoney Creek Invitational Championship.
During 2020–21 season in her sophomore year, she recorded two goals and three assists in 21 games, and helped the Badgers win the 2021 NCAA tournament.