Meet Your Student Services Staff



Ms. Heydi Baptista
Social Worker

Heydi Baptista has served as a school social worker in APS since 2003 and has been at Washington-Liberty High School since 2008. She has worked with students at the elementary, middle school, and high school levels. Ms. Baptista earned a Bachelor of Science degree in Social Work at George Mason University and a Master’s degree in Social Work at Howard University. Ms. Baptista is fluent in English and Spanish.


Ms. Brittnee Stephens
School Social Worker

Brittnee Stephens received a Bachelor’s Degree in Child Development and Family Relations at East Carolina University and a Master’s degree in Social Work at West Virginia University. Prior to coming to APS, Brittnee worked as a Medical Social Worker at Inova Fairfax Hospital. She is very excited to be working in APS especially at W-L. In her spare time, she likes to work out, eat and read books.


Ms. Monica Larrieu
Attendance Specialist

Monica Larrieu received her Bachelor of Individualized Studies degree in Art Therapy from George Mason University.  Additionally, she received her Master’s degree in School Counseling from Virginia Polytechnic Institute in 2002.  Prior to joining W-L that year, Ms. Larrieu worked as a Bilingual Outreach Specialist at Gunston and Swanson Middle Schools and at Oakridge Elementary School, and as an interpreter/translator for Arlington Public Schools.  She thoroughly enjoys her role as Attendance Specialist because it allows her to work closely with students and their families.  Ms. Larrieu is fluent in English, Spanish, and Portuguese.



Ms. Lori Ockerman
School Psychologist

Lori Ockerman joined the W-L staff in 2016, but has worked at various schools around the county as a psychologist since 1997.  She earned her BA from Morehead State University and her MA from George Mason University.  Prior to coming to Arlington, Ms. Ockerman served as an adjunct faculty member for  the University of Maryland in their European Division, and taught at the middle school level.  She enjoys travel, theater, concerts and cooking.


Dr. James Siddall

School Psychologist

James Siddall was born and raised in the DC area. He received his Bachelor’s degree in Psychology and Educational Studies from Washington University in St. Louis before attending the University of South Carolina where he received his Master’s and Ph.D. in School Psychology. His graduate work included working at the elementary and high school levels as well as working in a developmental pediatric clinic specializing in Autism diagnostics. He is very excited to be working in APS and especially at W-L! In his free time, he coaches a youth rugby team and enjoys staying active.

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Ms. Maria Luisa Ceballos
Substance Abuse Counselor

Maria Luisa Ceballos is a Licensed Professional Counselor and a Certified Substance Abuse Counselor. She received her Bachelor of Arts degree in Psychology from the Sacred Heart University in Lima-Peru. Additionally, she received her Master’s degree in Community Counseling from Trinity University in 1998 and completed a Post Master’s Program at George Mason University in 2007. Prior to joining Washington-Liberty as the School Substance Abuse Counselor, Ms. Ceballos worked as a Child and Family Therapist at the Arlington Department of Human Services where she provided mental health and substance abuse treatment services for thirteen years. Ms. Ceballos is fluent in English and Spanish.