Leadership Team

Head of School – Ms Elvan Tongal

Elvan Tongal is the Assistant General Manager of MEF Schools and the Head of School of MEF International Schools Istanbul and Izmir. She has 32 years of professional experience, including 17 years of administrative roles. She worked as a History Teacher in many private schools, notably the Founding Director of SEV American College. Specializing in the IB Diploma Program, Ms. Tongal has been the IB Workshop Leader since 2013. She also completed her certification program and was entitled as the IB Evaluation Team member in 2023. She has been working as a part-time instructor at the Teachers’ Academy Foundation (ÖRAV) since 2010. She has taken part in important projects such as ‘Sabancı University Alternative History Book Writing’, ‘No Teaching Limit’ and ‘Digital European Union: Turkish E-Book for High School and Primary School students. A graduate of Marmara University, Department of History, Ms. Tongal holds Sabancı University Alternative History Books and Bahçeşehir University Education Management and Supervision Master’s degrees. Elvan Tongal is a digital immigrant and a hopeful traveler on the path to learning.

Primary School Principal – Mr. Brett Warfield

Mr. Brett Warfield proudly serves as the Primary School Principal for MEF International School in Istanbul, marking his fourth year with the school. With over a decade of international school leadership experience, including nine years within the context of the International Baccalaureate, Brett remains passionately dedicated to nurturing the academic and personal growth of every student under his care.

A strong proponent of inquiry-based learning, creativity, student agency, and Positive Behavior Interventions and Supports (PBIS), Brett steadfastly believes in fostering an environment in which students are not only challenged academically but are also supported and inspired to realize their unique potentials. His leadership philosophy is rooted in collaboration; he actively engages with students, teachers, parents, and fellow leaders to cultivate a positive and effective learning community.

As a testament to his commitment to professional growth and excellence in education, Brett holds a Bachelor of Education from Missouri State University, a Certificate of School Leadership and Management from the Harvard Graduate School of Education, and has recently completed his Master’s Degree in Educational Leadership from the prestigious University of Bath.

In his personal time, Brett is an avid lover of nature and travel, valuing the diverse perspectives that these experiences bring. Whether exploring a new country or enjoying a quiet moment outdoors, he finds these activities to be a source of inspiration and renewal. Above all, Brett cherishes the time spent with his friends and family, grounding him in his values and purpose.

Secondary School Principal – Ms Nicole Roman-Incel

Nicole Roman-Incel is the Secondary Principal of MEF International School in Istanbul. She has lived in Turkey for 12 years, and has two sons. She has a B.A. in World History and Education from Loyola University of Chicago and an M.A. degree in TESL and Linguistics from Northeastern University of Chicago. She also has a Certificate in School Management and Leadership from Harvard University Graduate School of Education. Ms. Incel has been working in education for 21 years, twelve of which have been at MEF IS. In past years, she has taught World History, Humanities, Language Arts, and ELL English, as well as served as the Student Support Team leader and Deputy Principal. She is also the accreditation chair of MEF IS for the Council of International Schools (CIS) and New England Association of Schools and Colleges (NEASC). Ms. Incel is a firm believer that all students are capable of learning anything with the right tools and strives to support teachers with providing these tools to their students. She also believes MEF IS has a great community who always supports one another. Ms. Incel is interested in educational history, world history and differentiated learning. In her free time, she enjoys spending quality time with her family and exploring different parts of Türkiye and the world.

Primary School Deputy Principal – Ms.Gillian Davidson

Gillian Davidson is the Primary Deputy Principal of Istanbul MEF International School. She has been working in education for the last 10 years, two of which have been dedicated to MEF IS. Gillian demonstrates a commitment to fostering a positive and inclusive learning environment. 

Originally from Scotland, Gillian moved to Turkey 7 years ago and has made Turkey her home alongside her husband and two dogs. She has a Bachelor of Arts from the University of East London, and she is currently enrolled in the certificate program for School Leadership and Management at the Harvard Graduate School of Education. 

Having served as both an English Teacher and a Learning Support Specialist in the past, her educational philosophy revolves around enhancing inclusivity and nurturing independence in students. She firmly believes in the power of reflection and strives to instil strong moral values in students, guiding them towards becoming responsible and compassionate individuals. 

In her free time, Gillian enjoys taking leisurely walks, sailing, and spending quality time with her loved ones, Gillian embraces a holistic approach to life that reflects her dedication to both personal well-being and professional growth.

Secondary School Deputy Principal – Ms.Victoria Cerdas

Victoria Cerdas is the Secondary Deputy Principal of Istanbul MEF International School. She has been working in education for 13 years in Switzerland, Costa Rica, and Türkiye. For six years, she taught Early Childhood at MEFIS and was the ECC Team Leader for two years. This is her eighth year working at MEFIS and her second year as deputy principal. She holds a Bachelors in Early Childhood Education from UNED Costa Rica and is currently enrolled in the Masters of Advanced Teaching program at the University of the People in Pasadena, California. Victoria has an ability in fostering a caring and safe learning environment where students can initiate inquiry. Being a PYP-trained educator, along with her international experience, she is aware of the cultural and social context in which the children live and learn. Besides her teaching skills, she is multilingual. She speaks English and Spanish fluently, and has Elementary proficiency in German and Italian, allowing her to promote international-mindedness. In her free time, Victoria enjoys spending time with her family and friends, traveling, practicing yoga, and walking in the park. She is looking forward to another year with the MEF International School community.

IB DP Coordinator – Ms. Beliz Kearin

Beliz Kearin is the IB Diploma Program and Cambridge Diploma Program Coordinator of MEF Schools of Istanbul. She has 22 years of teaching experience, working with gifted students for 12 years and working as an IB teacher and IB examiner for 16 years and she is an IBEN Program Leader. She also worked as Deputy Principal, IB CAS coordinator, and Foreign Teacher Coordinator in her previous school. Recently, Beliz has been working as the Modern Foreign Languages Department Head at MEF International School, teaching French at both IGCSE and IB levels. Beliz has a French teaching degree from Istanbul University and FLE program from Strasbourg University. She has also received her NT Masters Degree in Learning Sciences from MEF University. As well as this, Beliz is especially interested in differentiated learning, gifted education and how dyslexia affects second language learners. Beliz is the mother of one daughter who also attends MEFIS, which helps her to understand parents’ perspectives and points of view for the educational needs of students. She enjoys traveling with her family all around the world where she loves to snorkel, scuba dive, and sample different cuisines.

Academic Dean and CAIE Programs Coordinator – Dr. Constance Bahn

Dr. Constance Bahn is the Secondary Academic Dean of MEF International School in Istanbul. She has lived in Turkey for four years. She has a B.A. in Secondary Humanities and is a certified Secondary Biology and Middle School Sciences teacher from Millersville University of Pennsylvania, a M.A. degree in Education in Curriculum, Instruction, Assessment, and Evaluation (CIAE) from Walden University, and a Ph.D. in Education in CIAE. Dr. Bahn has worked in education for 17 years, four of which have been at MEF IS. In past years, she has taught Earth Science, Humanities, Language Arts, PE, Physics, Middle school general science, Biology, Chemistry, IBDP Biology, IBDP Environmental Systems, and Societies, as well as served as the PBIS committee leader, Technology Leadership Team and science department head in her last school. Dr. Bahn is a firm believer that when you involve students in their learning, making decisions about how they learn, and answering their own queries, all students are capable of deep learning and engagement in the process of learning. She also believes MEF IS has an incredibly diverse community that engages in learning, supporting each other, and building and supporting all persons for success. Dr. Bahn’s Ph.D. focused on the implementation of inquiry-based learning strategies. Dr. Bahn has been interested in democracy in education, student and learner-centered teaching philosophies, and progressive education. In her free time, she enjoys scuba diving, listening to and practicing music, and exploring different parts of Türkiye and the world.

IB PYP Coordinator – Hala Hajj Sleiman

Hala Hajj Sleiman is the IB PYP Coordinator of MEF International School in Istanbul, bringing a wealth of experience and training to her role. With 6 years of international school experience, Hala has developed a passion for creating lifelong learners and empowering students to take ownership of their learning. As a pedagogical leader, Hala believes in building a culture of reflection, collaboration, and shared responsibility. In addition to her experience as a PYP Coordinator and homeroom teacher, Hala worked as an educational consultant, collaborating with non-governmental organizations to support teachers and schools with the integration of technology in their classrooms. In her free time, Hala enjoys activities that promote well-being, such as yoga, surfing, and camping.