Mrs. Lumsden has been the Principal of Hilltop Elementary since Fall of 2020. Mrs. Lumsden joined Argyle ISD in 2018 and served as an Argyle Middle School Assistant Principal for two years before becoming the Hilltop Principal. 

Before joining Argyle ISD, she served in Lake Dallas ISD from 2004-2018 and was promoted to Lake Dallas High School Assistant Principal in 2015 and held this position for three years. During her career, Mrs. Lumsden has served as a Math Teacher at the Middle and High school levels, Academic Advisor and led the Counseling & Advising Department at LDHS. She was named the Lake Dallas ISD Secondary Teacher of the Year in 2009-2010.