Key Personnel

Katie I. Ginsberg — Founder, Executive Director

Katie I. Ginsberg

Katie represents CELF to outside organizations and on committees, and at the local, state, national and international levels. She builds and maintains relationships with schools districts, outside experts and colleges in support of CELF’s mission and programs. Katie oversees and manages organizational development and assures that program objectives are met.

Katie has conducted and participated in a broad range of seminars, conferences and courses on sustainability and on re-orienting education through global and interdisciplinary education. She works with thought leaders in this emerging educational paradigm who are advising schools and educational systems worldwide. 

Katie is a Founding Member of the Westchester Green Schools Coalition and serves on the Westchester County Climate Change Advisory Panel. She served as Chair of the County Executive’s Westchester Global Warming Task Force for the education sector, which developed a blueprint to integrate sustainability across the campuses, curriculum and communities of Westchester, NY schools.  Ms. Ginsberg also serves on the Board of the Women's Climate Initiative and on the Advisory Board for Teatown Lake Reservation.

Prior to founding CELF, Katie was a founding partner and director of marketing for an accessories company. She previously worked in Account Management at BBDO Worldwide Advertising. Katie has a BA in Psychology from Northwestern University. 

Alan Cass — Director of Education

Alan serves as the Director of Education for CELF where he provides professional learning to K-12 teachers in public and private schools. During his classroom teaching career, Alan was both an elementary and middle school classroom teacher at several grade levels and in different subject areas as well an Assistant Principal. His belief in an interdisciplinary approach to learning is reflected throughout his work. While teaching middle school science and math, Alan spent two summers as a participant in NASA’s Educator in Space program where he created a Young Astronauts Program for grades 5-6. His work as a mathematics teacher led him to create several interdisciplinary programs such as Mall Math and the Math Chef, which he has presented at numerous National Council of Teaching Mathematics conferences.

Alan holds a BS degree in Elementary Education from Buffalo State College, an MS degree in Education from the State University at Buffalo, an MS in Educational Leadership from Pace University and he completed his Advanced Certificate in Education for Sustainability at Manhattanville College.

Holly H. Moskow — Director of Communications and Development

Holly spreads the word about CELF’s programs and supports the Executive Director on fundraising activities, working on development strategy for expansion and diversification of the organization’s funder base. Prior to joining CELF, Holly served as Executive Director and President of Sheldrake Environmental Center. She has volunteered for numerous environmental causes in her community. She completed the Westchester Master Composter and Recycler Program held at Sheldrake and has done community outreach and education on these topics. Holly held positions of increasing responsibility in marketing and brand management at Fidelity Investments, American Express and Colgate-Palmolive before leaving the corporate world.

Holly holds a BA in English and communications from the University of Pennsylvania and an MBA in marketing and finance from the J.L. Kellogg Graduate School of Management at Northwestern University. She also completed the Nonprofit Leadership program at Fordham University.

Jennifer M. Sheehy — Finance Manager

Jennifer is responsible for all the financial operations of the organization including financial reporting, budgeting, compliance and risk management. Prior to joining CELF, Jennifer was the Director of Finance and Development at the Housing Development Fund in Stamford, CT where she was responsible for their loan portfolio management, financial reporting and grant writing among other duties. As the Controller of the Loan Syndication and Trading Association in New York City, Jennifer had the opportunity to bring the accounting function in house, writing the accounting policies and procedures as well as the HR manual for the organization. She also participated in the Connecticut Department of Mental Health and Addiction Services year-long Leadership Institute designed to develop future executive talent in the non-profit sector.Before entering the non-profit sector, Jennifer spent ten years in finance and operations for a large health insurance company.Jennifer is a long-time community volunteer including nine years as a member of the Junior League of Northern Westchester where she served three years on their Board of Directors.

Jennifer’s educational background includes an MBA in Finance and Statistics and Operations Research from the NYU Stern School of Business and an undergraduate degree in Economics from Yale University.

Aimee Arandia Ostensen — NYC Program Manager

Aimee serves as the NYC Program Manager and she supports additional CELF professional development programs as a co-facilitator and co-developer with the director of education. Aimee is the Farm/School Coordinator for Special Projects at the Manhattan Country School and has taught both elementary and middle grades at MCS. Aimee firmly believes that learning is a life-long process and that our experiences along the natural path of life can be our best teachers. Her own path to teaching is a spiral of explorations into art, nature, movement and community. Aimee’s early experiences in dance created a foundation in aesthetic and kinesthetic awareness, as well as an understanding of creative and collective processes.

Aimee earned a BS in Early Childhood and Elementary Education at New York University, and a master’s degree in Educating for Sustainability at Antioch University New England. Whether in the forest, the city, at the farm, or traveling in another country, she seeks out the connections and dynamics within and between things, and strives to embody Kirkegaard’s notion that we are not merely human beings, but “human becomings.”




CELF Staff


Executive Director:
Katie I. Ginsberg

Director of Education:
Alan Cass

Director of Communication & Development: Holly H. Moskow

Finance Manager: Jennifer M. Sheehy

Project Manager:
Aimee Arandia Ostensen

Student Ambassador Coordinator: Anthony Patierno

Office Phone: 914.238.4743
Fax Number: 914.238.4743

Our Volunteers
make a Difference!

In addition to our committed full-time professional staff and our program coordinators, CELF is fortunate to have a cadre of dedicated volunteers and consultants who are vital to the success of our programs. If you are interested in volunteering with CELF please email us at

“[CELF’s] course was profoundly important to me. I was already committed to teaching kids about the environment, but this course drove my commitment up several notches. As a result of what I learned, I plan to change the focus of my enrichment class… to refocus on systems thinking, and imbuing the kids with an understanding of our ecosystem, and how various human activities affect it.”

  4th Grade Enrichment Teacher

Copyright 2014. Children’s Environmental Literacy Foundation. All Rights Reserved. CELF-taught is a Service Mark of CELF.