People

Kari Ostrem

Head of School

Kari Ostrem is Riverdale’s Seventh Head of School. She began her official position with Riverdale in July, 2023. 

Kari brings 25 years of experience to this position. She is a devoted educator, having spent her career at a combination of independent, public, and charter schools. She most recently served as the founding Head of School at the Haile-Manas Academy, the first nationwide residential school in Ethiopia dedicated to accepting students from different ethnic backgrounds. Kari built the academy from the ground up based on the principles of design thinking. 

During her extensive career in education, Kari has also served as Academic Dean at The Lawrenceville School in New Jersey, where she advanced the school’s strong academic and experiential programs; Co-Director and Co-Founder of the Bronx Lab School, a public school tasked with providing an innovative and rigorous college-preparatory education to students in the Bronx; and Director of Science for KIPP NYC, a public charter school in New York City, leading the design of a new curriculum based on critical thinking and data analysis for elementary and middle school students. Kari also has extensive teaching experience at both the high school level (math and science) and collegiate level (adjunct professor of mathematics education) and was a founding faculty member of The Island School. 

With her appointment as Riverdale’s next Head of School, Kari will continue to enthusiastically pursue the question of “how do we help kids thrive?”

And, Kari is passionate about deepening Riverdale’s connection with our neighbors in the Bronx, as well as expanding the School’s commitments to experiential education and sustainability. 

Kari is also an experienced engineer with a bachelor of science degree in Engineering from Princeton University and a master of science degree in Environmental Engineering from Columbia University.