Register for a Spring Tour Today! Sign up at a The 2022-2023 application is open! Apply now. Applications are accepted on a rolling basis. Please contact the admissions office to inquire.

Do not show this message again.

About Léman

Leadership & Faculty

Instructional excellence is a foundational pillar of the Léman experience. As a team of educators, our goal is to ignite children's passion for learning through superior teaching. Through one-on-one, small group, and differentiated instruction, our faculty members know and appreciate each student's unique interests, strengths, goals, and learning styles.

In addition to our nurturing and accomplished faculty, more than 80% of whom possess advanced degrees and credentials, Léman benefits from the expertise of experienced administrators and department chairs. We approach our practice with a shared mission: to help every child grow and succeed, and to build a community of the highest caliber teaching.

Our Teachers

Léman teachers do not simply provide superior instruction — our teachers lead, inspire, excite and relate to students in a caring, supportive manner.

We place intense focus on every child's learning experience, encouraging curiosity, accomplishment, and growth. Teachers at every grade level ensure that students engage deeply in content, build critical thinking skills, make connections between their work and the world, and enhance their skills to the greatest extent of their aptitudes and abilities.

Our team of educators is highly collaborative, working in grade level, department, and cross-curricular teams to cultivate best practice teaching methodologies and ensure curriculum is vertically articulated across grades to support each student's continuous growth. Léman teachers create nurturing, inclusive learning environments and teach to each child's interest and ability level every day, in each lesson, to achieve progress benchmarked to individual goals.

Léman teachers are energetic professionals who care deeply about their students and their own professional growth. They participate in professional development opportunities for continuous improvement throughout the year and are committed to honing their craft to enable our students to benefit from innovative educational practices. Léman teachers do not simply provide superior instruction, they lead and inspire students in a caring, supportive manner to help them realize their full potential.


Maria Castelluccio

Head of School

Ms. Castelluccio was named Head of School at Léman Manhattan in October 2015 and began her term in July 2016. A proven educational leader and visionary, Ms. Castelluccio has dedicated her career to driving student performance and building community in PreK-12 schools in the U.S. and internationally for more than 25 years. She joins Léman after four years as the Head of School at Marymount International School of Rome, also an International Baccalaureate School, where she developed and carried out a strategic plan that increased IB scores to 98% pass rate and 45% of students scoring in the top 20th percentile worldwide.

From 2009-2012, Ms. Castelluccio served as Marymount Rome's Elementary School Principal, where her accomplishments included introducing Columbia University Teachers College Reader's and Writer's Workshop and Responsive Classroom, and advancing the academic rigor of the educational program. For more than a decade prior to Marymount Rome, Ms. Castelluccio held senior administrative roles at high-performing elementary schools in Westport and Stratford, Connecticut. She began her career as a 3rd and 4th Grade teacher. Ms. Castelluccio holds a Bachelor of Arts in Intermediate Education, Magna Cum Laude, from Southern Connecticut State University; a Master of Science in Science Education from Southern Connecticut State University; and a Sixth Year Degree in Administration and Supervision from Sacred Heart University. Originally from the Bronx, Maria raised her four children in Fairfield County, Connecticut. She is an avid reader, and when she has the time, loves to travel, walk and practice yoga.

Maria Sweeney

Director of Curriculum & Interim Head of the Center for Early Childhood Education

Maria Sweeney is Léman's Director of Curriculum, as well as Head of the Center for Early Childhood Education (CECE). Mrs. Sweeney serves as the academic dean for PreK-12th grade, working closely with the academic division heads to further develop and implement curriculum consistent with our school mission, vision, core values and IB philosophy. Mrs. Sweeney joined Léman from Oakhill Academy in Temecula, CA, where she was Head of School from 2015-2019. Previously, Mrs. Sweeney was the Curriculum Coordinator PreK-12 and then the Early Childhood and Elementary Principal at the Marymount International School of Rome from 2007-2015. For more than 25 years before joining Marymount, Mrs. Sweeney served as an administrator and classroom and ESOL teacher in schools across the world. Mrs. Sweeney holds the following educational credentials: Bachelor's Degree in Psychology from Loyola Marymount University in Los Angeles; Teaching Certificate from University of California, Los Angeles; Master's Degree in Curriculum and Instruction from University of California, Riverside; Post-Master's ESL Certificate in English as a Second Language from Eastern University, St. David's; and Principal's Certificate in Educational Leadership from The Principal's Training Center. Outside of Léman, Mrs. Sweeney likes to read, cook, travel and spend time with her family. Her daughter is a student in Léman's Upper School.

Jerry Maraia

Head of Lower School

Dr. Maraia joined Léman in 2013 as Head of Curriculum, Instruction, and Assessment. In that role, he served as the academic dean across PreK-12 with a focus on four major areas: Curriculum, Instruction, and Assessment; Teacher Recruitment, Retention and Development; Student Support Services; and Accreditation. In partnership with the Head of School, divisional leaders, and department heads, Dr. Maraia led the development of curriculum to best support measurable student outcomes and Léman's mission, vision, and values as an International Baccalaureate school. He was appointed Assistant Head of School in 2016 and Head of Lower School in 2017. In the Lower School, Dr. Maraia leads the daily operations of the division and academic program for Kindergarten through Grade 5, focusing on developing children's skills in reading, writing and mathematics, and building fluency across fine arts, science, and world languages. Working collaboratively with the Upper School Leadership, Dr. Maraia also spearheads the transition process to Middle School to support the academic, social and emotional success of every child.

Prior to joining Léman, Dr. Maraia was a curriculum consultant and staff developer at the Teachers College Reading and Writing Project at Columbia University where he consulted in private and public schools across New York City, the United States, and around the world. Previously, Dr. Maraia taught English at the Clinton School for Writers and Artists. He is a frequent presenter at national conferences and universities on curriculum and instruction, and adjunct professor in elementary education and educational leadership programs. He received his Bachelors from Skidmore College, followed by a Masters from New York University, and a Masters from Bank Street College of Education. Dr. Maraia received his Doctorate in Educational Leadership from the University of Pennsylvania.

Eric Hawthorn

Head of Middle School

In his role as Head of Middle School, Mr. Hawthorn has a focus on working with middle school students (grades 6-8), and serves on the upper school leadership team to build community across grades 6 through 12, spearhead new initiatives and special projects, and develop programming that supports students academically, socially and emotionally.

Mr. Hawthorn joined Léman in Fall 2014 and taught both Middle School and High School Social Studies and launched a new Student Ambassador program. After one academic year, he was promoted to the Assistant Head position. Prior to joining Léman, Mr. Hawthorn taught Social Studies, P.E, and Health in charter and private schools in the New York City area. Originally from the U.K., Mr. Hawthorn holds a B.A. in Education with a specialization in History and Physical Education. Outside of school, Mr. Hawthorn enjoys exercising, reading, watching and coaching soccer, listening to music, and spending time with his three godchildren.

Steven Lyng

Interim Head of High School

Steven Lyng, Ph.D., a seasoned IB educator and administrator with more than 25 years of experience in secondary education and 16 years of leadership roles in International Baccalaureate schools, joined Léman in 2021 as Interim Head of High School. For the last 10 years, Steven has held senior leadership positions at Windermere Preparatory School in Orlando, FL, including Head of School, Assistant Headmaster and High School Director.

At Windermere, Steven successfully led the implementation of the IB program which resulted in pass rates of more than 90% in just two years and top-tier college admissions. As Head of School, he has led a faculty and staff of more than 200 and spearheaded Windermere’s online learning and reopening during Covid. Prior to Windermere, Steven served for six years as the High School Principal at Northridge High School, an International Baccalaureate High School in Middlebury, IN. Previously, he was High School Principal and Assistant Principal at Rochester High School in Rochester, IN. He began his career in education as a social studies teacher. Steven holds a Ph.D. in Educational Leadership from Purdue University, an M.S. in Educational Administration from Indiana University and a B.S. in Education from Indiana University.

Demetrius Laffitte

Upper School Dean of Students

Demetrius Laffitte serves as the Upper School Dean of Students. As Dean of Students, Mr. Laffitte takes the lead in supporting students and faculty regarding all discipline issues in the high school, including academic dishonesty. Mr. Laffitte oversees student clubs and activities in the High School as well as oversees the planning, logistics and scheduling of the high school advisory program and more.

Mr. Laffitte joined Léman in 2017 as Assistant Athletic Director and physical education instructor. He has 22 years of teaching experience, which includes many accomplishments as a teacher of physical education, health and science, and as a basketball, football and volleyball coach. Mr. Laffitte has worked at schools in San Diego, Milan and Rome, most recently at Marymount International School. He also played 12 years of professional basketball throughout Europe and South America. Mr. Laffitte has an MSc degree in education from Asuza Pacific University and a BA in physical education from United States International University. Demetrius and his wife, Barbara Pluchino-Laffitte, have three sons - Dominic, Daniel, and Diego, who are Léman graduates and students.

Luz Garcelon

Director of International Baccalaureate (IB) Programming

Luz Garcelon joined Léman in 2021 from the United Nations International School (UNIS) in Manhattan, where she served as the IB Diploma Coordinator since 2015. At UNIS, Ms. Garcelon supervised the IB program to promote academic success, oversaw the organization of IB exams and evaluations, coordinated teacher professional development and partnered closely with parents and administration to support student achievement. During this time, she also served as a Spanish teacher for grades 6-12. From 2011 to 2015, she held other leadership roles at UNIS including Student Engagement Team Leader and UNIS-UN Faculty Advisor.

Prior to UNIS, Ms. Garcelon led the IB program as IB Program Coordinator at Santiago College School in Santiago, Chile, an IB World School serving students in preschool through grade 12. She began her education career at Santiago College School as an English Teacher, where she instructed higher level and standard English classes to prepare students for IB external and internal assessments.

Megan Storey Hallam

Director of Student Support Services

Mrs. Hallam is responsible for leading Léman's Learning Support Department, supervising and coaching learning support specialists, school nurses, school counselors, and the school psychologist. This dedicated and experienced team of resources is committed to the academic and social/emotional well-being of each student and supports students across PreK-12 in achieving success and flourishing at Léman. In addition, Mrs. Hallam serves as the Student Support Services Department Chair.

Mrs. Hallam has more than 20 years of experience in PreK-12 schools in the U.S. and around the world. Prior to Léman, she oversaw student support at The Washington International School, a leading PreK-12 International Baccalaureate World School in the D.C. area. Mrs. Hallam served as the Lead School Psychologist at Marymount Rome International School for three years. Mrs. Hallam also worked at the University of Pennsylvania researching child development, publishing studies in Pediatrics, Obesity and the Journal of Nutrition. Mrs. Hallam supports various volunteer positions dedicated to building resilience in military populations and providing education and health-related support to underserved populations. In recent years, she has led volunteer programs for high school students in Peru, Costa Rica and Zambia.

Mrs. Hallam holds an M.S. in Psychology from Villanova University and an Ed.S in School Psychology from The College of William & Mary and is also pursuing an Ed.D in Educational Policy, Planning and Leadership. Mrs. Hallam and her husband have two children, a daughter attending Swarthmore College and a son who attends high school at Léman. During her free time, she enjoys yoga, running and traveling with her family. Her son graduated from Léman in 2020.

Lisa Nowicki

Director of Fine Arts

Ms. Nowicki oversees all curricular and extra-curricular programs in Visual Arts, Music, Theatre, and Film for Léman Manhattan. Prior to coming to Léman in 2011, Ms. Nowicki served as the Performing Arts Department Chair at the Sanford School in Hockessin, DE, where she worked for 19 years and produced award-winning music ensembles and a nationally recognized Theatre program. In Theatre, Ms. Nowicki has worked as a musical director, producer, and conductor. She is the co-founder of Delaware All-State Theatre®, the nation's only All-State Theatre organization for students, and serves on their Board of Trustees. In addition, she is a former chairperson of the DAIS Music Educators group, which involves 23 schools in DE, PA, MD, and NJ. Outside of education, Ms. Nowicki has worked in corporate arts administration and has served as an Associate Producer for “Lisa Howard: Songs of Innocence & Experience, The Songs of William Finn” (Ghostlight/Sh-K-Boom Records). Ms. Nowicki received a B.S. in Music Education from West Chester University and a Masters in Educational Psychology from Widener University. She has graduate credits in music history from the University of Salzburg in Salzburg, Austria. Apart from her interests in music, theatre, and film, she enjoys reading, baking, and travel.

Keith Sequeira

Director of Athletics

Keith Sequeira leads athletic opportunities for students school-wide at Léman, including team sports in grade five, to elite level varsity sports at the high school level. During his time at Léman, Mr. Sequeira has grown the athletic program significantly, from 8 teams in 2009, when he joined the school, to 36 teams today. In his leadership of the athletic program at Léman, Mr. Sequeira builds a culture of community, sportsmanship and physical well-being across the school community. Mr. Sequeira brings a wealth of knowledge of New York City school athletic programs, from his Adjunct Professor position at St. Francis College in Brooklyn, as well as his positions as Athletic Director, Physical Education Chair, Admissions Director, Summer Camp and After School Director at schools in New York and New Jersey. Mr. Sequeira earned a B.A. in Physical Education from Hofstra University and a Masters in supervision from Adelphi University. Outside of his duties at Léman, Mr. Sequeira is on the board of the Old Bridge Girls Soccer League, where his daughters participate in the soccer program. He enjoys quality time with his wife and two daughters, as well as the most recent addition to their family, "Bubba" the mini pincher.

Scott Thompson

Chief Operating Officer

Scott Thompson leads the business office, facilities and technology teams to help support our school's continued innovation and growth. An experienced finance and strategy executive in the education industry, Mr. Thompson has held various executive leadership and chief financial officer roles both domestically and internationally and has also served on numerous boards of directors. He holds a BA in Accounting from University of Wisconsin-Whitewater and a Global Executive MBA from the Fuqua School of Business at Duke University. Mr. Thompson lives in Lower Manhattan with his wife Laurie and son Sloane, who is a Léman high school student.

Ahsan Karim

Director of Technology

Mr. Karim oversees all aspects of educational technology at Léman and drives the school's strategic vision for leveraging technology to enhance student learning. He has oversight for all technology systems that support student information, enrollment management, scheduling and grading, faculty collaboration, parent communication, and the cultivation of technology skills that prepare Léman students for an interconnected, digital world.

An IT professional with over two decades of experience in educational technology and technology support, Mr. Karim brings many years of teaching and administrative experience to our school. Prior to joining Léman, Mr. Karim spent 25 years at The Buckley School on the Upper East Side, where he managed all hardware, software, systems, and infrastructure initiatives, including the implementation of makerspaces. He also has extensive experience in developing and leading technology professional development workshops for faculty and staff. Throughout his career, he has taught coding, robotics, and circuit building in grades 1-9.

Mr. Karim holds a bachelor's degree in Computer Science from The College of Staten Island. He is a Google Certified Educator and also a Microsoft Certified Systems Engineer. He lives with his wife and daughter in Forest Hills, Queens, and during his free time, Mr. Karim enjoys cooking, reading and traveling with his family.

Steve Levin

Director of After-School and Summer Programs

With over 20 years of experience developing children's programming in New York City, Steve Levin leads Léman's after school and summer programs. With a broad array of offerings ranging from chess to math club to tennis, our after school programming complements the Léman academic program to harness the interest of every child. In addition, Camp Léman, for both Léman students and children in the community, is one of Lower Manhattan's premier programs for children, enrolling over 270 children each summer. Prior to joining Léman in 2008, Mr. Levin served as the Director of Camp Programs at the 92nd Street Y, and as camp director in the Poconos. Mr. Levin spent four years on the adjunct faculty of Fordham University's Graduate school of Social Service and has been a speaker and co-chair for various regional and national camping conferences. Mr. Levin has a B.A. in Psychology from Northwestern University and a Masters in Social Work from Hunter College. Outside of his work at Léman, Mr. Levin enjoys travel, running, exploring New York City, and the New York Times crossword puzzle. He currently lives in Brooklyn with his wife and two daughters who are both students at Léman.

Paige Murphy

Head of Marketing, Communications and Community Engagement

In partnership with faculty, students and parents, Mrs. Murphy leads Léman’s marketing and communications initiatives to build a dynamic and engaged community of families. She has oversight for all internal and external school communications, including publications, PR, social media and digital, school events, and community relations throughout Lower Manhattan.

Since joining Léman in 2014 as Head of Marketing, Admissions & Communications, Mrs. Murphy has helped establish Léman as a leading Manhattan private school and grow enrollment to 900 students. Mrs. Murphy has worked closely with thousands of New York City parents to help them navigate the admissions process and find the right school for their child.

Mrs. Murphy joined Léman after more than 15 years in education communications, both in K-12 and higher education. For nearly a decade, she was a senior marketing executive at Kaplan, one of the world's leading providers of educational services, where she oversaw global brand development. Previously, she was Assistant Director of Communications at Columbia University.

Mrs. Murphy holds a B.A. in Political Science and French from Colgate University. She lives in the Financial District with her husband and two sons, who are students at Léman in the Lower School. Outside of school, Mrs. Murphy enjoys cooking, travel, and architecture.

Alexandra Whelehan

Director of Admissions

Mrs. Whelehan leads PreK-12 admissions at Léman, advising families with children as young as toddlers through high school to discover the distinctions of a Léman education. Mrs. Whelehan is responsible for managing all aspects of the admissions process, from strategic enrollment management planning and execution of ongoing admissions events to interviewing families, performing student interviews and assessments, and leading Admissions Committee and Financial Aid reviews. She represents Léman at independent school conferences and events and collaborates with Léman faculty, parents and students to continue to grow the Léman community.

A native New Yorker, Mrs. Whelehan is a graduate of The Town School and The Dalton School. She has 20 years of experience in independent school administration, having held senior admissions and financial aid positions at Dwight School, Rodeph Sholom School, and The Town School. In addition, she has served as Director of Development and Alumni Relations at Buckley Country Day School and Director of Admissions and Marketing at East Woods School in nearby Long Island. She has also served on the ISAAGNY Board of Trustees and on the Board of the Association of Teachers in Independent Schools. Mrs. Whelehan holds a B.A. in English from Kenyon College and did graduate work in English Education at New York University. She lives in Long Island with her husband and three children and enjoys playing tennis, cooking, and sailing with her family.

Joshua Anchors

Director of Global Admissions and Residential Life

Joshua Anchors collaborates with the school's partners from around the world to bring talented, motivated international students to Léman Manhattan. As the director of Léman's unique boarding program, Mr. Anchors is also responsible for the academic and socio-emotional well-being of 120 students from over 20 different countries. Originally from Maine, Mr. Anchors worked in disaster relief for a variety of organizations including the United Nations, FEMA, and the Louisiana Recovery Authority, before transitioning into education. Prior to working at Léman Manhattan, he taught at Saint Ann's School, the Brooks School, University Laval, and the University of Strasbourg. Mr. Anchors holds degrees from Columbia University, Boston University, and the University of Maine. Outside of his work at Léman, he enjoys bicycling, sea kayaking, and creative writing.

Debbie Aragon

Head of Human Resources

Debbie Aragón leads the Human Resources Department at Léman by leading benefits analysis and administration, compensation, staff training & development, workers’ compensation, safety training, employee relations, performance management, organizational development, and HRIS. Ms. Aragón has over 15 years in human resource management and prior to Léman was Head of Human Resources at TAO Group, VP of HR at Dean & Deluca, Director of HR at Max Brenner, and the US HR Administration Manager at Le Pain Quotidien. She holds a Bachelor of Arts degree in Psychology from Hofstra University, a Human Resources accreditation from Pace University and is a member of the Society for Human Resource Management (SHRM). A Queens native, she currently lives on Long Island with her three children and two Persian cats and enjoys crafts, yoga, and spending time on the beach with her family in the summer.

Explore the Léman experience for your child.

Request More Information
Instagram YouTube
International Baccalaureate
World School
New York State
Association of
Independent Schools
Accredited by
Middle States
Association of
Colleges and Schools
Parents League
Parents League
of New York
Member School