Sierra Lopez de Castilla was hired as a Learning Specialist in August of 2022. In her current role, she assesses the needs of at-risk student athletes, develops plans and teaches skills to aid in student academic success. Previously, she worked at ACU as the Football Academic Coordinator (June 2021-August 2022). Before working at ACU, she worked for two years as a fifth grade teacher at Wylie West Junior High in Abilene.

Lopez de Castilla earned her master's degree in teaching and learning in 2019 from Abilene Christian, and also spent her undergraduate years at ACU earning her bachelor of science in interdisciplinary studies (early childhood through sixth grade) in 2018.

Lopez de Castilla was a student-athlete at ACU in both cross country and track from 2016-2018. 

Lopez de Castilla is passionate about serving student-athletes and is married to Robert Lopez de Castilla, the coordinator for small groups and discipleship at ACU. Robert and Sierra welcomed little baby Christian this past year, ACU's number one fan.