Our People

Shawn Mangar, Founding Principal

Shawn Mangar is an educational leader, who builds school culture that fosters trust and inspires the development of both students and staff. He is known for driving organizational excellence and conquering every obstacle with a novel approach. Starting his career as a special education teacher, Shawn followed his passion for developing others by becoming a top-rated NYC Teaching Fellow trainer. He is founder and principal of the award-winning Baychester Middle School in the Bronx, which develops not only distinguished scholars but also extraordinary teachers, 5 of whom have already become national educational leaders.

Shawn and his school, Baychester Middle, have been featured on the Teaching Channel, in Quanta and Wired magazines, and in books, such as The Together Leader: Get Organized for Your Success - and Sanity! and Teach Like a Champion 2.0: 62 Techniques that Put Students on the Path to College. He has served on the Mayor’s Leadership Team on School Climate and Discipline and is a sought-after speaker for education programs on data-driven instruction and teacher training. Having been born, raised, and educated in the district where he works, Shawn explores new horizons in long training runs for his many marathons.

Rebecca Arsham, Assistant Principal

Rebecca Arsham is a school leader who has the goal of fostering a strong school community for students, staff and families. She attended University of Maryland where she got her bachelor's degree in family science. She further pursued her love for education in 2016 when she joined Teaching Fellows and Relay Graduate School for Education. She has taught as a special educator in a range of subjects and settings within 6 - 8th grade. She is passionate about ensuring that all students are able to learn grade-level material, and encouraging students to have confidence and pride in their unique abilities. In December of 2020, Rebecca received her degree in Progressive Leadership from Bank Street. Most recently, She has worked as a Teacher Leader in the 2020 - 2021 school year, focusing particularly on creating positive school culture. At Baychester Middle School, her field of work revolves around school culture; specifically advisory curriculum, school events and incentives, as well as systems surrounding student behavior.

Staff Directory