Jo Lynn and Sandi each began their career as diagnosticians under the tutelage of their friend, mentor and fellow diagnostician, Carolyn Pendleton, M.Ed.. While working in Allen ISD, Jo Lynn and Sandi had the privilege to work closely with behavioral pediatrician, Dr. Paul Warren. When Dr. Warren asked Jo Lynn, and later Sandi, to work for him doing diagnostic assessments in his private practice, they both eagerly embraced the opportunity to work with such a knowledgeable, compassionate and spiritual man. Dr. Warren’s death in 2006 challenged the diagnosticians to move out on their own, while still respecting his spirit and contribution to their private practice career. Dr. Warren’s legacy of child-centered, compassionate care was instrumental in helping Jo Lynn and Sandi define the type of services they wanted to continue offering students in the DFW area. In 2007, Grace Evaluation was formed to help brand the services they had been providing. Dr. Warren’s philosophy of “relationships come first” became the foundation for Jo Lynn and Sandi, as well as the other wonderful practitioners at Preston Family Practice. The Grace Evaluation team chose to further their reach in the community by moving their practice to downtown McKinney, TX in 2013. The move to McKinney affords them closer proximity to their homes and the opportunity to create and add new relationships in the McKinney, Allen, Frisco and surrounding Collin County areas.

Jo Lynn Wilburn, M. Ed.

Jo Lynn was a “military brat” who graduated from Randolph Air Force Base High School. She attended Southwest Texas State University and received a Bachelor’s of Science degree in Education with an endorsement in Special Education. Jo Lynn taught Special Education classes in Spring Branch ISD, in Houston, as well as in Plano ISD. After staying home with her children for a few years, she returned to school to obtain her Master’s of Education degree at Texas Woman’s University in 1993. Jo Lynn became an Educational Diagnostician in Allen ISD where she worked for nine years before entering private practice in 2001 with Dr. Paul Warren and his associates. Because her years as a diagnostician in Allen ISD were spent at middle school and high school campuses, she specializes in testing students at the secondary and college level. She lives in Allen with her husband, Craig and has three grown children and two young grandsons. She is a member of the Council for Exceptional Children.

You may contact Jo Lynn Wilburn at or her direct line: 972-646-2732

Sandi Frost, M. Ed.

Sandi grew up in Plano and was a graduate of Plano Senior High School. She attended Southwest Texas State University in San Marcos, TX and received her B.S. in Education, with a major in Special Education. After teaching special education in both Dallas and Carrollton-Farmers Branch ISD, Sandi obtained her Masters of Education from Texas Woman’s University in 1994. Sandi served as a school educational diagnostician in both C-FBISD and Allen ISD for seven years. Since 2002, she has been in private practice with Jo Lynn and her associates at Preston Family Practice. The majority of Sandi’s experience has been spent working with elementary aged students and their families. She is a member of Texas Professional Registered Educational Diagnosticians, Texas Educational Diagnosticians Association (TEDA). Sandi and her husband, Chuck, currently reside in Allen with their youngest daughter, Kennedy. She also has an older daughter, Taylor.

You may contact Sandi Frost at or her direct line: 972-646-2733

Associates of Grace Evaluation
Sharon Wright, M.Ed.

You may contact Sharon at

Olga Pace, M. Ed.
Olga was born in Maryland, lived in South America and did most of her growing up in El Paso, Texas. She attended Texas Tech University where she received her Bachelor of Arts in Speech, with a major in Deaf Education and minor in Elementary Education. She obtained her Masters of Education from the University of North Texas in Special Education, while also earning her certification as an Educational Diagnostician. Olga started her teaching career in East Texas (Mt. Pleasant and Longview) before moving to Plano, TX with the Plano Regional Day School for the Deaf program. Being able to speak conversational Spanish and use sign language was an asset when she became an educational diagnostician in 1994 for Plano ISD until 2006, when she became a Special Education Coordinator for McKinney ISD. One of Olga’s primary duties as a coordinator was to oversee the evaluation team of Diagnosticians and LSSPs, which allowed her to stay current on evaluation research and methodologies. This position coincided with the beginning of her daughter’s kindergarten year in MISD. Olga worked until December 2013 when she retired from the public school system with 31 years of experience. Being retired has allowed Olga to be more available while her daughter was in middle school and now high school. She started working at Grace Evaluation with Jo Lynn and Sandi in the spring of 2014 and feels it’s been a privilege and a blessing to continue to work with children of all ages, their families, and be able to work in a positive, professional, and spiritual environment in the private sector. Olga resides in McKinney with her husband and daughter.
You may contact Olga at

Tara Taliaferro, M.Ed.
Tara grew up in Oklahoma and received her Bachelor’s of Science degree in Special Education from Southwestern Oklahoma State University in Weatherford, Oklahoma. She taught students with special needs in both Oklahoma and Texas. She received training through the Texas Scottish Rite Hospital for Children to become a dyslexia therapist and is a Certified Academic Language Therapist. She is a member of the Academic Language Therapy Association. Tara attended Texas Woman’s University where she received her M.Ed. in Special Education with Educational Diagnostician certification. She has worked with students and their families as a dyslexia therapist and an educational diagnostician, in elementary, middle school, and high school levels.
You may contact Tara at