Skip to Main Content

Achievement First Achievement First

The Achievement First Leadership Team

We started with a single school. Now we’re 15,000 students strong. As we continue to grow and better serve those students, our leadership team is at the helm of this important work of transforming public education in America.

Our leadership team is made up of content specialists, leadership coaches, operations experts, financial wizards, former teachers and principals, and all around champions for kids.

Meet our leaders.

  1. Lisa Margosian

    Chief Executive Officer

    Lisa is Achievement First’s Chief Executive Officer and works closely with the AF boards and leadership team to ensure academic and operational excellence across our 41 schools and three regions. Her focus is on improving the strength of AF schools and building the infrastructure to enable the network’s continued expansion with quality and shape our future roadmap.

    Lisa joined AF in May 2022 as Interim CEO and transitioned to CEO in August 2023. Prior to this, she served as the Interim CEO of Ascend Charter Schools. While there, Lisa led between the organization’s founder and now permanent leader during the global pandemic. With more than thirty years of experience with for-and-non-profits, Lisa developed a deep understanding of all facets of leadership, which includes developing high performing leadership teams, leveraging stakeholder management skills, rebuilding underperforming businesses, leading businesses through integration post-mergers, scaling nonprofits, and transforming organizations after mission shifts. Lisa also served as KIPP’s Chief Program Officer and Director of Network Growth and Chief Customer Officer of the Girl Scouts of the USA. Prior to that, she led businesses in financial services with Bank of America and JP Morgan Chase.

    Lisa, a proud Wisconsin native and child of public school educators, has always had a deep and abiding passion for K-12 education. She believes the key to social justice and racial equity is quality education that creates access for all children. She has a bachelor’s degree from Marquette University and an MBA from Columbia Business School. Lisa has made New York City her home with her husband and two children.

  2. LaNelle Alexander

    Chief Equity Officer

    LaNelle Alexander has a legacy of leading significant organizational development, culture and diversity, equity, inclusion and belonging efforts for nearly 20 years across international non-profits, for profits, and higher education based on her deep commitment to advancing equity and combating the pernicious legacy of systemic racism by leading healthy culture transformation.

    LaNelle is a mission-driven leader, workshop facilitator and leadership coach who has a track record of designing and infusing DEIB and Racial Justice strategies to help organizations create healthy cultures, cultivate positive engagement and drive business success by building more resilience and equitable environments, systems, practices and programs so their people and people leaders are empowered with tools and resources to remove systemic barriers to individual and collective success.

    Most recently, she served as the inaugural Head of DEI where she was a member of the senior team, responsible for designing and executing a multi-year DEI-AR strategic plan, executing, leadership and team coaching, leadership development workshop, driving organizational alignment and sustainable change impacting teams aligned to Mission, Vision and Values.

    Prior, LaNelle was on the executive leadership team at buildOn, an international nonprofit based in Stamford, CT, where she served as their first Vice President of Human Resources and founding Global Director of Equity, Diversity & Inclusion (EDI).

    LaNelle holds a BA in Organizational Behavior and Change Management, with a concentration in Diversity and Inclusion from New York University.  She is an ICF certified professional coach (CPC) specializing in executive leadership and team coaching from iPEC. She also maintains certifications from both the Society of Human Resources [SHRM-CP] and Society for Diversity [CDP].

    LaNelle is also on the board of buildOn NY, a nonprofit focused on youth development in the South Bronx and HOPE Worldwide’s CT Chapter, which delivers sustainable, high impact community-based services to vulnerable local and international communities.

  3. Tiffany Bostic

    Chief of Support Services

    Tiffany is a dedicated and visionary leader who is passionate about improving outcomes for students and helping them achieve their full potential. She is an accomplished licensed clinical social worker and holds a Bachelor of Arts degree from Clark Atlanta University and a Master of Social Work degree from Howard University.

    Tiffany began her career at AF in June of 2020 as the Director of Social Work. In just three years, she has made a significant impact on the organization, expanding the mental health program and network support. Under her leadership, the mental health program grew from 48 to 65 mental health clinicians, and a senior director of social work was added to the team. Additionally, she created a talent pipeline for social workers and counselors with the establishment of an internal clinical supervisor program. Tiffany also codified and strengthened social worker and counselor professional development and practice systems, increasing capacity and strengthening whole school collaboration.

    Prior to joining AF, Tiffany served as a middle school social worker at Bedford Stuyvesant Collegiate for six years. During her tenure, she expanded the social work department, built out community partnerships, and created a male mentorship program, which has proven highly successful.

    In her free time, Tiffany enjoys bike riding throughout Brooklyn, trying new restaurants, binging podcasts and mindless television shows and traveling.

  4. Kristin Damo

    Chief of Elementary Schools

    Kristin comes to this position with almost two decades of experience in education and a dedication and commitment to our students and communities. She is currently a Regional Superintendent and supports both elementary and middle schools. Prior to joining Achievement First in 2021, Kristin was a middle school principal at Success Academy Charter Schools. Before entering into leadership, she has held a number of positions within education, including as a high school advanced placement teacher, instructional coach, and Teach Plus leadership fellow. She holds a B.A. from Carleton College and an M.A. from Columbia University, Teachers College. In her spare time, she enjoys exploring Brooklyn with her partner and children, as well as their dog, Thor.

  5. Xanthe Jory

    Chief Operating Officer

    As the Chief Operating Officer, Xanthe leads teams involved with school operations, systems and data, information technology, and facilities. Previously, Xanthe served as the Chief Planning and Policy Officer at the NYCDOE’s Division of Early Childhood Education during a period of time when the City’s early childhood system was expanding to serve every four-year old in New York. Xanthe is also the founder of Bronx Charter School for the Arts, and served as the school’s leader for eight years. Xanthe’s previous experience additionally includes working with various educational organizations on initiatives related to teacher evaluation, alternate certification, principal selection, systems design, program design, knowledge management, compliance, policy, expansion, and quality assessment. Xanthe holds a bachelor’s degree in Urban Studies from Stanford University and master’s degrees in teaching and school leadership from CUNY Lehman College and the Harvard Graduate School of Education.

  6. Charmayne Joseph

    Chief of Middle Schools

    In her role as Chief of Middle Schools, Charmayne works to elevate the quality of the middle school academic and student experience, a critical time of transition in child development. She has spent the last 18 years working across K-12 in a variety of roles including teacher, school leader, Regional Superintendent, and Associate Chief of Student Experience. She has experience across founding, fully grown, and turnaround schools. Charmayne started her education career in 2005 and holds a Bachelor of Science in Human Development and Family Studies and Masters in both Curriculum and Instruction and Special Education.  Charmayne is originally from Brownsville, Brooklyn, a mother of four beautiful children (including a set of fraternal 3-year-old twins) and spent her K-12 education attending public schools.  She deeply loves this work and is grateful for the opportunity to continue her life’s calling of dismantling systemic racism within education and beyond. She looks forward to learning, growing, and continuing to support our schools together.

  7. Omar Mayyasi

    Interim Chief Financial Officer

    Dr. Omar Mayyasi comes to Achievement First with over two decades of financial and operational experience in education.  As CFO, Omar leads Team Finance in overseeing the organization’s fiscal health, positioning it for sustainable growth and impactful educational outcomes.  Omar brings a wealth of expertise in financial management, strategic planning, and operational efficiency, underscored by a commitment to educational access and student success.  His approach to fiscal management is grounded in data analytics and stakeholder feedback, ensuring that financial strategies align with the institutional mission and strategic objectives.  Omar’s passion for education is rooted in his belief in the transformative power of education to foster social justice and racial equity.

    Prior to joining Achievement First, Omar held leadership roles at various education institutions, including an independent school, a community college and a private higher education institution.  Omar earned a Bachelor’s degree in Business Administration from the American University of Beirut, and a Doctorate in Economics and Education from Columbia University.  He is also a Certified Public Accountant, licensed in New York and Florida.  Omar resides in Westchester County with his family, where he is actively involved in the community, coaching youth soccer and serving as a trustee on the board of education in his district.

  8. Dumar Paden

    Chief of High Schools

    In his role as Chief of High Schools, Dumar leads AF’s approach to improving HS academic results through goal setting, progress monitoring, and performance management and ensuring the development and execution of our long-term high school program vision. Dumar has nearly two decades of experience as an educator and school leader and specific expertise in building successful high schools. At Achievement First, Dumar has served students at  AF University Prep HS as an Academic Dean, the Principal of AF Brooklyn High School, and a Regional Superintendent. During his tenure at AF Brooklyn High, he led his school through the height of the pandemic, increased pass rates, AP performance, Org Health, and dramatically reduced the number of suspensions. Before arriving at AF, he served as the Director of College & Career Readiness at New Dawn Charter School, an alternative transfer high school serving over-aged and under-credited students who were not successful in traditional educational settings. Prior to his work at New Dawn, Dumar served in a variety of capacities within education including work as a School Counselor, Writing/Composition teacher, and manager of several non-profit programs. Born and raised in Brooklyn, Dumar was the first male in his family to graduate from college. He obtained his Bachelor of Science from The State University of New York at Albany, and his Master of Science from Grand Canyon University. His experiences growing up in Brooklyn as a first-generation college graduate keep him committed to his community while ensuring youth receive quality education opportunities.

  9. Michael Rabin

    Chief Strategy and Growth Officer

    Michael comes to the Chief Strategy and Growth Officer role with thirteen years of teaching, school leadership, and regional leadership experience in Washington D.C and at Achievement First. He served as the Founding Assistant Principal at Rocketship Rise Academy before becoming the Founding Principal at Rocketship Legacy Prep. He then served as the Associate Director of Schools with Rocketship DC, where he led the region’s COVID recovery and reopening, school leader development, and regional operations, while also supporting wellness initiatives, systems-level coordination and strategic planning, and project management across the entire Rocketship Public Schools network. Michael joined Achievement First in March 2022 as the Associate Chief of Staff and has had the opportunity to collaborate with staff across Network Support and within the schools in all three regions on a variety of projects including charter renewals, school contingency planning, portfolio management, and more. Michael is originally from Chicago and now lives in Fairfield, CT with his wife Monica, two daughters Devon (6) and Blair (3), and yellow lab puppy, Clementine. 

  10. John Sharkey

    Chief Academic Officer

    In his role as the Chief Academic Officer, John leads the vision and development of academics, curriculum, and quality instruction across K-12. John came to Achievement First (AF) in 2020 as the Vice President of Great Teaching, Middle School (MS) where he supported the design and implementation of both our Greenfield and Classic ms models. He holds a Master’s in Teaching and is completing his dissertation on the acceleration of reading proficiency in secondary students at Johns Hopkins University (JHU). Prior to joining the organization, John was a middle school English teacher and assistant principal. John also previously worked in teacher preparation with Urban Teachers at JHU as the National Director of Literacy. He believes access to high-quality, evidence-based, and culturally empowering curricula is a fundamental right for our schools and the communities they serve. He is excited to forward AF’s foundation into the future and looks forward to the partnership with leaders, teachers, and families as we work to continue building an exceptional and cohesive vision for teaching and learning.

  11. Ru Sharma

    Chief People Officer

    Ruchika (Ru) Sharma comes to Achievement First with 20 years of Human Resources experience across the United States, Asia, Europe, and Africa. She has held senior leadership roles in HR at renowned multinational corporations, including Coca-Cola, Amazon Web Services, and Bloomberg. Ru’s expertise encompasses leading large, complex global HR teams, building in-house HR technology solutions, as well as coaching senior leaders and teams. As a “third-culture kid” who was raised in various countries, Ru is particularly passionate about fostering diverse leadership and inclusive cultures. She holds a Bachelor’s degree in Information Technology and an MBA with a specialization in Human Resources.