Before attending Seton Hill, Keagan was a four-year varsity starter for the Caledonia High School Women’s Lacrosse team. As a freshman, she received First Team All-State Honorable Mention. Sophomore, junior, and senior year, Keagan earned First Team All-State, along with All-Conference awards all four years.
Her senior year she was named First Team All-American to finish off her high school career. During her last high school season games, she became the all-time leading career goal scorer in the state of Michigan with 287 career goals.
Along with playing lacrosse, Keagan also played basketball as her second sport. She ended her senior year by being named Female Athlete of the Year class of 2014 for Caledonia High School.