From July 1, 2025, the Headmistress of the International European School Warsaw named after Jan Kułakowski is Mrs. Marzena Wieczorek.

Mrs. Wieczorek is a graduate of the Warsaw University of Technology, where she obtained her Master’s degree in Automation and Computer Engineering. She has completed postgraduate studies in mathematics as well as in educational management and education policy. She holds teaching qualifications and is a certified teacher.