Instructional Leadership Team


CGJames Willett

Senior Assistant Principal of Instruction

Mr. Willett was born in a small town in the outback of Australia where he spent his school years. Upon graduating from high school, he attended the University of Newcastle, balancing his love of mathematics with his love of sports and travel. Since becoming a teacher, he taught in both England and Australia before joining the MESA team in 2016. In his spare time, you will find him searching the country for amazing outdoor activities.









Krystal Mieschberger

Director of Instruction

Ms. Mieschberger is a New York native! Before moving to Brooklyn, Ms. Mieschberger grew up in Suffolk County, Long Island. During her time there she graduated from Hofstra University with a double major in both Mathematics and Mathematics Education. Since 6th grade, Ms. Mieschberger has been inspired to be a mathematics teacher and has continued to follow that dream by teaching, coaching & furthering her own education. Ms. Mieschberger graduated with her Master's Degree from Touro College and is now a part-time professor there! When she is not teaching you can catch Ms. Mieschberger eating Oreos, playing with her doggy Lexi, and practicing her Minion impressions!








JBJessica Bloom

Director of Student Supports

Ms. Bloom grew up just outside of New York City. She attended Syracuse University where she majored in pre-medical studies and nutrition science and minored in psychology. After college, Ms. Bloom began teaching as a member of the 2011 Teach for America Corps where she worked as a Special education and science teacher with 9th through 12th graders. During this time she completed her master’s degree at Hunter College and participated in the Sci-Ed Fellowship where she gained additional experience in facilitating students’ active engagement in science, including participation in a  science fair. During her free time, Ms. Bloom enjoys dance, yoga, and outdoor summer activities.




JSJohn Sullivan

Director of Teacher and Student Development

Mr. Sullivan grew up on the beaches of Central New Jersey (no he did not go to high school with any cast members of the Jersey Shore). He has recently moved back to the NYC area after five years of teaching at a charter school in Massachusetts. Prior to that, he was a founding teacher at the Williamsburg Charter High School. In his free time, he enjoys going on day trips and adventures with his wife and two sons. He enjoys hiking, snowshoeing and having a healthy obsession with meteorology. Urban planning, architecture, street design, and neighborhood observations fill the rest of what little time he has left each day. As a huge believer in what communities can accomplish, cooperation and compassion, he is very excited to be a part of a team that displays so much of both!