Active on the boards of many community organizations, she was inducted into the Colorado Women's Hall of Fame in 2018.
[2] Starting at age 8, she entered 4-H competitions and eventually competed at the local, state, and national levels.
[1] In 1973, she was one of two students from the state selected to participate in a six-month International Farm Youth Exchange program in Taiwan arranged by 4-H.[2][3] She left a week after earning her undergraduate degree.
Her visit coincided with a typhoon, and she witnessed the resiliency and coping mechanisms of people in that situation.
[2] Horrell began her career as a high school teacher in Adams County, Colorado.
[4] After a brief retirement, Horrell re-entered academia in 2016 to become Chancellor of University of Colorado Denver.
She was a founding member of the board of Arrupe Jesuit High School (2003-2011) and Clyfford Still Museum (2005-2013), chair of the Board of the Colorado Association of Funders (2009), and co-chair of the Commission on the Reform of Denver's High Schools (2004–05).