Sandi is a native of Warner Robins, Georgia, and a graduate of Northside High School. She attended the University of Georgia where she obtained a Bachelor of Business Administration majoring in Management Information Systems, and Georgia College and State University where she obtained a Master of Business Administration. Sandi is married to her high school sweetheart, Rob Couillard.  They have two sons, Jordan and Payton (both Northside High School graduates) and a daughter-in-law, Tracy who is a HoCo graduate.

Her career began at GEICO in Macon, Georgia, where she held positions as Automobile Claims Adjuster, Renewal Underwriter, and Claims Coverage Underwriter (expert trial witness). Upon leaving GEICO, she worked as the first paid Executive Director for the Central Georgia Soccer Association where she wrote and was awarded a $25,000 Atlanta Falcons Youth Foundation Grant on behalf of CGSA.

In 2004, she began her education career at Northside High School serving as a Business and Computer Science Instructor (14 years).  She also served as Work-Based Learning Coordinator, FBLA Advisor, and Career-Technical Department Chairperson.

Sandi currently serves as the Youth Apprenticeship Coordinator for Houston County Schools with her office at Houston County Career Academy.  She spends her days forming and maintaining partnerships with businesses in the middle Georgia area with her goal to obtain and continue job placements for high school students. She also prepares students for jobs by assisting them with resume and cover letter creation, and practicing job interview skills and trains educators on helping their students prepare for the workforce. Working with young people is Sandi's passion and when asked about her job, she says, "Each day provides another great opportunity to help a young person move toward his/her dreams. There is no better career than this!"

During the 2019-2020 school year, Sandi served as West-Central Region Co-Chairman on the State Executive Board for the Georgia Work-Based Learning/Youth Apprenticeship Affiliate and was one of twenty WBL Coordinators to be selected into the Work-Based Learning's Top Gun Program. Excitingly, Sandi was named the 2020 West-Central Region Work-Based Learning Coordinator of the Year and her WBL student was named the 2020 State of Georgia Work-Based Learning Student of the Year.  For the 2020-2021 school year Sandi served as the Chairperson of the West-Central Region of WBL,  her student won Youth Apprenticeship Completer of the Year, and her Principal, Sabrina Phelps, won the Georgia's Work-Based Learning affiliate CTAE Administrator of the year after Sandi's nomination.  In 2022, Sandi's student, Kristin Woodard (HCHS) was named Georgia's Work-Based Learning Student of the Year!  Mrs. Couillard is always excited to see her students and administrators succeed.