A 2025 graduate of Founders Classical Academy, McConnell competed as a thrower for the Spartans at the 1A level under head coaches Ramsey, Parrish, and Stockton. The native of Honolulu, Hawaii captured 1A conference titles in both shot put and discus as a senior, along with a state runner-up discus finish.

The four-year letterwinner set the discus program record (108-2) during her junior season, then broke her own mark at the state meet in 2025 (110-10). She helped lead the Spartans to a third-place finish at the conference meet and seventh at the state champions in her final season.

Mackenzie is the daughter of Larry and Olivia McConnell and hopes to major in kinesiology.