Board of Trustees


Meet the Prospect Sierra’s Board of Trustees, who set school governance policies, focuses on long-range and strategic issues and ensures the ongoing vitality of the school.

ruth200x300Ruth Bissell

Ruth uses her anthropological training to coach teachers and support diverse, equitable educational experiences that have included leading educator workshops at the Museum of the African Diaspora in San Francisco and being the Upper Head of School at The San Francisco Day School. Ruth also serves on the Board of Directors for Beyond Differences, a national nonprofit focused on ending social isolation and providing positive experiences for students in middle schools. She is a foodie, sport-shopper, and loves to travel with her husband, Matt and two children, Alex and Ryan.


Emily Bruce

Emily Bruce brings teaching and administrative experience in higher education to Prospect Sierra. A former lawyer, she currently is the Director of Equity and Inclusion in Berkeley Law’s student services office, where she provides educational programming and serves as a resource for students, faculty, and staff seeking to promote a culture of belonging and cultivate a holistic sense of well-being. Emily is a meditation teacher and yoga practitioner, and although she has lived in five states and four countries, she will never tire of exploring her home state of California. Her daughter is a student at Avis and her son is a Prospect Sierra alum.

Charlie Casey, Board Chair

Charlie has an extensive background as the Director of Technology at both Maybeck and Lick-Wilmerding High Schools, also spending many years teaching math, computer science and band. A captain licensed with the US Coast Guard, Charlie enjoys sailing excursions in locations such as Hawaii, Phuket, Dalmatian Islands and, most recently, the Hebrides Islands.




Jenny Chatman

Jenny Chatman is a professor at the Haas School of Business at UC Berkeley. She specializes in organizational behavior, conducting research and consulting focused on leadership and cultivating an effective organizational culture. She and her husband Russell Barnett have two daughters – Ava (’12), now a student at Cornell University, and Sonya (6th). They are proud to have been a part of the Prospect Sierra community for a very, very long time!



Kate DeYoe

Kate has over ten years of experience in both international and domestic microfinance, most recently as a Project Manager at Opportunity Fund, a nonprofit that delivers affordable and responsible loans to small business owners who have been left behind by traditional financial institutions. Previous work in the field includes roles at the Silicon Valley Microfinance Network, Kiva, Truelift, SaveTogether, and Full Circle Fund. Earlier in her career, she provided Financial Advisory Services at Deloitte and PwC. A Chicago native, she earned her BS in business administration from Bucknell University. Kate enjoys hitting the outdoors – on foot, bike, skis, you name it – most especially with her family, which includes a 6th grader at Prospect Sierra and a newly minted alumnus.

Andrew Dreskin

Andrew Dreskin is the co-founder and CEO of Ticketfly, Inc., a leading live events technology company, which is owned by Pandora, Inc. Prior to Ticketfly, Andrew was the co-founder and CEO of TicketWeb, the first company to sell event tickets online. Prior to that, Andrew was the Executive Vice President of Beserkley Records, an influential independent record label. Andrew holds a BA from Tulane University, and serves on numerous Boards of Directors including Headcount, a non-partisan non-profit organization that works with musicians to promote participation in democracy. 
Andrew has been active on the Finance Committee and has two children attending Prospect Sierra in the 5th and 7th grades.



Yohance Edwards

Yohance became the first Director of Workplace Relations in the federal judiciary when he joined the U.S. Courts for the Ninth Circuit in January 2019. Prior to his appointment, he was the Associate Director and Deputy Title IX Officer in the Office for Prevention of Harassment and Discrimination at the University of California, Berkeley, where he oversaw the process for resolving complaints of discrimination and harassment based on race, color, national origin, age, gender, sex, sexual orientation, and gender identity, including allegations of sexual harassment. He also conducted trainings on the university’s harassment and nondiscrimination policies and procedures and helped coordinate campus compliance with Title IX of the Education Amendments of 1972. Prior to his time at UC Berkeley, Yohance was an attorney at the United States Department of Education’s Office for Civil Rights.  Yohance received his BA from Brown University and his JD from New York University School of Law. Yohance’s daughter Soleil is a student at Avis.

Nathalio Gray

Nathalio has over 14 years’ experience in independent school education, specializing in community service, diversity and inclusion, summer programs, and admissions. He is currently the Director of Admissions at the Branson School. In addition to his work in schools, he is a Youth Pastor serving the West Oakland community, paying close attention to raising awareness and eliminating gun violence. He and his wife are committed to their faith, family, community, and also have a passion for sports



Brian Greenberg

Brian Greenberg is the CEO of the Silicon Schools Fund, a non-profit investment fund launching the next generation of personalized learning schools in the Bay Area of California. Brian is a former charter school founder, Chief Academic Officer, and worked previously as a classroom teacher, in politics on statewide and national campaigns, and in higher education at Carnegie Mellon University. Brian received his BA from Dartmouth College and an M.Ed. from Harvard University. Brian has been active on the Finance Committee and has two children attending Prospect Sierra in the 3rd and 6th grades.


Liz Maw

Liz serves as the President of Presidio Graduate School, the nation’s leading MBA program focused on sustainability and social justice.  Prior to Presidio, Liz was the CEO of a global nonprofit organization called Net Impact that engages young adults in social and environmental projects and careers. Liz has served on several nonprofit boards and is thrilled to currently lend her expertise to Prospect Sierra’s Development Committee. She has two sons, including a Prospect Sierra 6th grader.

Jennifer Morgan

Jennifer Morgan is the vice president of operations and marketing for Stop Meeting Like This – a leading collaboration consultancy revolutionizing the way teams and organizations work. Prior to her current role, Jennifer spent more than 20 years in senior corporate communication and investor relations roles within the institutional financial industry.  Jennifer grew up in the Bay Area, and is a graduate of the University of California at Berkeley.  Jennifer is on the committee of trustees, and she and her husband have two sons attending Prospect Sierra in the 3rd and 7th grades.

Delphine Sherman

Delphine Sherman is the Chief Financial Officer of the Haas School of Business at UC Berkeley and oversees the Finance and Financial Aid teams. Prior to joining Haas, Delphine was the Chief Financial Officer of Aspire Public Schools, a national charter school management organization headquartered in Oakland, serving over 17,000 predominantly low income K-12 students. Delphine received her BA from Dartmouth College and an MBA from UC Berkeley. Delphine has been active on the Finance Committee and has three children attending Prospect Sierra.

Dana Tillson

Dana sharpened her business skills during two decades in the apparel industry, working in budgeting, auditing, management, process improvement, and negotiations with The North Face and Sierra Designs. She serves on the the Board’s Committee on Trustees and the Finance Committee. Her two children, Gillie and Leo, graduated from Prospect Sierra. Outside of work, she competed internationally in rowing, which fueled her lifelong interest in health and fitness, especially road cycling and mountain biking.


Denise Yamamoto

Denise brings social enterprise and nonprofit experience to Prospect Sierra. She is currently serving her 3rd year as a trustee and on the Committee on Trustees and Development Committee. She has a BA in Economics and East Asian Languages from UC Berkeley, and an MBA from the Haas School of Business and is originally from Oxnard, California where she grew up on a farm. In her free time, Denise likes to ride her bicycle in the Oakland hills, chase her kids down the slopes in Tahoe, and drink wine with her husband.