Executive Director

Thor Snilsberg


Thor Snilsberg is a parent, educator, and social entrepreneur dedicated to inspiring a generation of urban youth to learn from and improve their environment. Born on a farm and trained as an urban planner, Thor has led economic development, alternative transportation, and education projects with community engagement at their heart. By bringing science to life in their communities, Thor envisions a world where students learn and apply science in their surroundings.

Thor’s engagement in education issues began as an undergraduate when he first volunteered as a mentor, tutoring middle-school students in St Paul, MN. After moving to NY, Thor continued to mentor youth and volunteer for educational organizations. These experiences developed Thor’s commitment to educational equity and his desire to found CityScience.

As the founding Director, Thor draws from his prior work in all three sectors of the economy. He began his career in technology consulting at Andersen Consulting (now Accenture) and worked as a labor market analyst before enrolling at Cornell University for a Masters in Urban Planning. While at Cornell, Thor conducted and published research on the early childhood economic sector.

To connect with Thor, .(JavaScript must be enabled to view this email address) or find him on LinkedIn.

Coaches and Assistant Coaches

CityScience Coaches and Assistant Coaches bring teaching experience and in depth scientific knowledge to your educational setting. To learn more about joining the CityScience team, visit our Jobs page.

Liz Castelli

Liz is a certified middle school science teacher who has been teaching in East Harlem and Washington Heights since 2006.  A true scientist and teacher, she earned her B.S. in Biology and Mineralogy and her M.Ed. in Secondary Science Education from The George Washington University and Columbia University. After working in the research laboratories of the Smithsonian Institution, she became involved with the civil engineering and astrophysics departments at Columbia where she continued doing research and sharing her laboratory experiences with her students. In 2010, she was selected to spend a summer researching algae as an alternate biofuel on the Great Barrier Reef in Australia. Most recently a master teacher with Equity Project Charter School, she is thrilled to bring her experience mentoring teachers and excitement for field-research to her coaching engagements with CityScience.

Alice Kasten

AliceAlice taught middle school science as well as regents earth science and regents bio in a NYC Middle School for 34 years. One of the original NYS earth science mentors, she has conducted hundreds of hours of professional development workshops. As the science consultant for a major textbook company, she later had the opportunity to edit review material and align them to New York standards, and continue professional development workshops nationwide. Alice is most proud of her relationship with the New York State Science Olympiad. As both a Board member, and the NYC Coordinator for the Middle Level Olympiad, she helps to bring hands-on science to students in middle schools city-wide. Alice also supervises student teachers, and helps in the construction of Earth Science Regents Examinations. She holds a BA in Biology from William Smith College, and a MA in Bio Education from Hunter College.

Alexandra Walker

Originally from New Jersey, Alex is currently a student at St. John’s University, pursuing a Masters in School Counseling. At St. John’s, she is an active member of the counseling honor society, Chi Sigma Iota (CSI) and other school-community programs like St. John’s GEAR UP. After graduating from Seton Hall University with a degree in Special Education, Alex has had experience teaching in various types of classrooms including resource rooms, inclusion based classes, and regular education. In her spare time she loves to volunteer at her local Boys and Girls Club and Care One Stations as well as coaching her very own 4-5th basketball team. Alex considers science to be one of the most important aspects to any curriculum. Science is a way for anyone to become more in tune with themselves and the world around them. She is passionate about many things, but helping others and making a difference in the community is probably the most important.

Danielle Butler

DanielleDanielle Butler is a New York native, born in Harlem and raised in the Throgs Neck section of the Bronx. Danielle is currently finishing up her B.S. in biology from Stony Brook University. Residing in Harlem for the past ten years she has had the opportunity to have over four years of experience tutoring and working with students ages 5-13 years old. Her goal is to become a cardiothoracic surgeon, science has always been one of her greatest passions. When Danielle is not wrapped up in science related topics, her interests expand into poetry, dance, and craft projects.

Robens Bien-Aimé

Robens_headshotRobins is a mechanical engineering student at the City College of New York. He was raised in Haiti until the age of 18. In middle school, a classmate of Robins demonstrated some electricity concepts using a light bulb and a battery. It is one of the reason he decided to learn engineering. In addition to his studies, Robins runs on the track team and is working as a tutor for the Academic Support Center of the College Discovery program at Queensborough Community College.

Alfonso Perez

Alfonso_Bio_PicAlfonso earned his master’s degree in Elementary Education from Mercy College through the New York City Teaching Fellows Program. For 11 years, he taught science in grades 2 through 6 in various schools across the city. He also spent a summer teaching STEM lessons at a public school in New Delhi, India, a unique experience that strengthened his belief that all children deserve an excellent education. In 2009, he became the co-founding 5th-grade science teacher at The Equity Project Charter School where he gained experience conducting frequent classroom observations, mentoring new teachers, and collaborating with his colleagues to create exciting, interdisciplinary projects. Alfonso loves planning outdoor learning opportunities for his students, such as taking them on school-yard trips to examine local rock formations or helping them design and build their own edible garden. He also enjoys using his graphic design skills to produce engaging WebQuests and online research projects for his students.


Program Manager - Matthew Patrick

Matt_headshotBorn in Staten Island and residing in Brooklyn, Matt is an experienced after-school educator with eight years of experience in OST settings. He firmly believes that every student in his native New York deserves an excellent education and that project-based learning is the key to achieving that standard.

Matt holds a B.A. in Cultural Anthropology from Hunter College where he was active on both the Faculty-Student Disciplinary Committee and the Undergraduate Linguistics Association.  Before coming to CityScience Matt completed two Americorps years with City Year New York.  Serving in middle school classrooms and leading corporate volunteer events illuminated the needs of teachers and the myriad of ways we can support them.

Matt continues to serve City Year New York by serving on the Alumni Board as the Alumni Engagement Committee Chair.  In his (rare) spare time he volunteers for New York Cares, enjoys exotic foods across the city, and has recently begun to brew his own beer.

Communications Associate - Courteney Palis

CourteneyCourteney is a native of New Jersey and recently received her MFA in fiction at Sarah Lawrence College. As an undergraduate at New York University, she studied journalism, environmental studies, and creative writing while working as a team leader for Jumpstart, an AmeriCorps program promoting language, literacy, and social emotional skills in preschool-aged children. Her writing has been featured in such print and online publications as the Galveston Daily News, Scholastic’s MATH and DynaMath Magazines, and The Huffington Post. While she isn’t helping CityScience to spread its message, Courteney is teaching college writing at SUNY Purchase College and working on turning her thesis into a finished novel.

STEM Consultant - Marlene Braha

Marlene was born and raised in Brooklyn, and is currently a student at NYU Polytechnic School of Engineering, studying Chemical and Biomolecular Engineering. Marlene enjoys tutoring high school students and helping them see their potential in science and math. Her favorite subjects are math, physics, and chemistry. In her free time, she enjoys bike rides, solving Rubik’s cubes, and playing Sudoku. In the future, Marlene wants to become a process engineer for a pharmaceutical company.

STEM Consultant - Juan Nizama

Juan is an undergraduate Biology major at Hunter College with a talent for organic chemistry and the goal of attending medical school. He was one of the first counselors at Steve’s Camp at Horizon Farm, a place that provides an escape for underprivileged New York City youth. He is part of the Community Of Unity family, a non profit organization dedicated to helping youth graduate high school. Juan lives in Bushwick, Brooklyn where his childhood love for science began. Always curious about how the world around him works, he spent hours at the park collecting bugs, climbing tries, and rummaging through the park for weird shaped things. Bringing his understanding of urban life and science expertise to CityScience, Juan seeks to hone his educator skills so he help children develop a passion for science.

CityScience Interns

CityScience believes in creating meaningful internships for high school students with a passion for science while also supplementing a wide range of professional experiences for graduate and undergraduate students.  To learn more about CityScience internships, visit our jobs page.

Check out these past volunteers to see how you could help at CityScience!

Out of School Time learning that connects learning to the daily lives of students. David Gelman After-School Coordinator