Gravitas teachers are engaging, supportive, dedicated, mission-driven experts in their fields. Here’s what our students have to say about them:

"All the teachers and faculty members are engaging and always show interest in students and their classes. The classes are intensive and rigorous, but all the teachers support you to a degree where all the work and studies become manageable."

"My class was pretty intensive, but my teachers were very supportive and helpful with the assignments and projects given to me throughout the week. Not only with assignments but during class, they were very engaging and were some of the greatest teachers I had."

"Great teachers for every class."

Sam Ahn Headshot Collage

Sam Ahn
Director of Passion Academies

Ed.D in Progress in Instructional Technology and Media, Teacher's College, Columbia University
Ed.M in Instructional Technology and Media, Teacher's College, Columbia University
MA in Computing in Education, Teacher's College, Columbia University
BA in Economics, UCLA

Sam is currently the director of Stony Brook School’s Gravitas Passion Academies and has more than 16 years of experience in the global private education industry – startups, franchises, and companies that went public – with significant global entrepreneurship experience. Most recently, Sam was the Director of the Institute for Technology, Innovation, and Entrepreneurship at Miss Porter’s School, an all-girls boarding high school in Connecticut, where he was the architect, taking a concept to the signature program that focused on inspiring and empowering young girls to be the future change makers that the world desperately needs. Sam has also specialized in top college admissions consulting with nearly a thousand students having matriculated to top-25 universities and continues to work with students around the world in facilitating an entrepreneurial mindset to tackle global problems. 

His educational background is in edtech and instructional design. Sam has two master’s degrees (Ed.M & M.A.) and is currently an Ed.D. candidate at the Teachers College, Columbia University. His research interests include using game dynamics and mechanics to engage learners and make learning fun. His lifelong goal is to continue designing engaging, authentic, and immersive real-world problem-solving-focused educational experiences for all learners. 

Sam Echevarria-Cruz Headshot Collage

Sam Echevarria-Cruz
Statistics Faculty

Ph.D in Sociology, The University of Texas at Austin
Ph.D in Business Management, Bucharest University of Economic Studies
MA in Sociology, University of Texas at Austin
BA in Sociology, University of Texas at Austin

Dr. Sam Echevarria-Cruz started teaching Advanced Statistics for Gravitas in 2023. In addition to teaching for Gravitas, Dr. Echevarria-Cruz also teaches statistics and quantitative research methods at Texas State University, a variety of courses in the Divisitions of Health Sciences and Business and Communications at Concordia University Texas, and has served as Professor of Sociology and Social Work, Associate Dean of Diversity, Equity, and Inclusion Initiatives in Instruction, and Dean of Liberal Arts, Social & Behavioral Sciences for Austin Community College. Dr. Echevarria-Cruz was elected President of the Faculty Senate for the Austin Community College District, and served on the American Statistical Associations Anti-Racism Task Force. Dr. Echevarria-Cruz was a Fulbright Scholar in Romania and has done research for a variety of programs, including Feeding America. He is heavily involved in youth ministry at Park Hills Baptist Church. He lives in Austin with his wife and five sons.

James Grant

James Grant
Spanish Faculty

MA in Spanish Language and Culture, NYU Madrid Campus
MBA Liberty University
BA in Spanish and Communication, University of Georgia

In 2023, James Grant left his position as chair of The Stony Brook School's World Language department to begin a position as an Assistant Professor of Modern Languages at Liberty University, but he decided stayed on the SBS Spanish faculty for Gravitas. James's career includes teaching Spanish at Davidson Day School in North Carolina, teaching online for Liberty University and Columbia International University, and serving as a missionary in Asturias, Spain through World Witness, Foreign Board of the Associate Reformed Presbyterian Church. At The Stony Brook School, James taught upper level Spanish classes and served as a dorm dad. He lives in Virginia with his wife, Rachael, and their five children.

Christina Howland

Christina Howland
Science Faculty

Data Wise Leadership Institute, Harvard Graduate School of Education
Masters of Public Health, The George Washington University
BS in Biology, Widener University

Christina Howland joined the Gravitas faculty in 2022 having previously served as the Program Coordinator for Aerospace Engineering & Aviation Technology at Prince George's County Public Schools. Prior to that, she was the Science Department Chair and Professional Development Lead Teacher at DuVal High School. Christina teaches a wide range of science courses for Gravitas, including Biology, Advanced Biology, Chemistry, Advanced Chemistry, Earth Science, Physics, and Advanced Environmental Science. She lives in the Houston, Texas region with her husband and children.

Meredith Kohlbrenner

Meredith Kohlbrenner
English Faculty

M.Ed in Curriculum and Instruction, American College of Education
BA in English Secondary Education, Grove City College

Meredith Kohlbrenner joined the Gravitas faculty in 2023 as our English 5/6 teacher. Mrs. Kohlbrenner previously served as the Curriculum Coordinator, Technology Integrator, and Teacher at Eastern Christian School in New Jersey. Prior to that, she served as an English Language Arts teacher at Amity Regional Middle School. Some of Mrs. Kohlbrenner's career accomplishments include designing and launching the Gifted & Talented and STEM programming at Eastern Christian Elementary School, facilitating the completion of Curriculum Mapping at Eastern Christian School District, and creating an engaging and supportive classroom environment where students felt safe taking risks. Mrs. Kohlbrenner lives in Franklin Lakes, New Jersey with her husband and two daughters. She indulges in sushi and chocolate as often as possible. Her family attends Grace Redeemer Church.

Maria Ibanez-Alvarez

Maria Ibañez
French Faculty

MA in English Philology, Universidad Autonoma de Madrid

Maria Ibañez-Alvarez joined the Gravitas faculty in 2023 as our French I and II teacher. She serves several other online schools as a French, Spanish, and English teacher and recently won a teacher of the year award. Prior to teaching online, Ms. Ibañez-Alvarez taught and developed curriculum at Franklin High and Sylvan Rodriguez Elementary, The English Centre in Puerto de Santa Maria, Spain and at Math and Science Leadership Academy in Denver, Colorado. Having grown up in Madrid, Ms. Ibañez-Alvarez began her teaching career in Europe, where she served as Head of Department of Modern Languages and Coordinator of International Relations at Kolbe International School. Maria currently lives in Miami, Florida. She loves to travel, watch dolphins, serve in her church, and go on missions trips.

Gravitas faculty member, Landon Loftin, who won the Owen Barfield Literary Estate Award for Excellence

Landon Loftin
English, History, and Bible Faculty

Ph.D in Humanities, Faulkner University
MA in Apologetics, Houston Baptist University
BA in Religion and Philosophy, Southwest Baptist University

Landon Loftin has a B.A. in Religion and Philosophy from Southwest Baptist University, an M.A. in Apologetics from Houston Baptist University, and a PhD in Humanities from Faulkner University. His publications include an assortment of peer-reviewed articles on the work of authors such as G.K. Chesterton, C.S. Lewis, and Owen Barfield. He recently co-authored a book called What Barfield Thought: An Introduction to the Writings of Owen Barfield for which he became a co-recipient of the Barfield estate's 2023 Award for Excellence. Prior to teaching, he served as a hospital chaplain. Earlier still, he and his wife lived and worked in Ghana where they helped establish a home for previously trafficked girls. He now lives in Bolivar, Missouri with his wife (Kate) and children (Eleanore Jane, Soren Wulfram, and Leo Alexander).

Joqui Giron-Melendez

Nancy "Joqui" Girón-Meléndez
Dean of Students
Spanish Faculty

BA in Middle School Education and Spanish, Gordon College

Nancy "Joqui" Girón-Meléndez serves as a Spanish teacher for Gravitas. Joqui graduated from Gordon College in 2011 with a double major in Middle School Education and Spanish. Upon graduating, she returned to her high school alma mater, Boston Trinity Academy, to serve as a Spanish teacher for 10 years. In that decade, she taught levels 1 through AP to grades 6-12. As a language teacher, Joqui strives for her students to include Spanish into their persona, challenging students to view language acquisition as a pathway to practice loving their neighbor. In addition to her passion for language acquisition, Joqui has a passion for student leadership and has led training on leadership and character development. Joqui has held various leadership roles throughout college and her 10 years at Boston Trinity Academy, including serving as the Dean of Students. In May 2019, she received the Boston Trinity Academy Alumni Recognition award, which highlights how an education at Boston Trinity Academy prepares students for leadership and service in college and beyond. Outside of school life, Joqui is an avid reader of fiction and social justice, seeking ways to understand how to love her neighbor. She and her husband are currently expecting their first child!

Zach Manis

R. Zachary Manis, Ph.D
Director of Character Formation
Humanities Faculty

Ph.D in Philosophy, Baylor University
MA in PHilosophy, Texas A&M University
BA in Philosophy, Hendrix College

Zachary Manis (Ph.D., Baylor University) is Director of Character Formation and Humanities Teacher for Gravitas. He is an academic philosopher by training, with areas of expertise in philosophy of religion, Christian ethics, and Kierkegaard studies. Dr. Manis is the author ofSinners in the Presence of a Loving God: An Essay on the Problem of Hell (Oxford University Press, 2019), as well as numerous peer-reviewed articles. He is coauthor, with C. Stephen Evans, of Philosophy of Religion: Thinking about Faith, Second Edition (IVP Academic, 2009). Prior to joining the Gravitas team in 2021, Dr. Manis taught philosophy at a Christian liberal arts university for sixteen years. He lives in Bolivar, Missouri with his wife Lisa and their three children: Solomon, Nora, and Emmaline. In his spare time, Dr. Manis enjoys spending time with family and friends, discussing philosophy and theology, reading, and playing drums.


Sean A. Riley, Ph.D
Executive Director
Philosophy Faculty

Ph.D in Philosophy, Baylor University
MA in Philosophy, The Pennsylvania State University
BA in Philosophy, The Pennsylvania State University

Sean Riley serves as the Executive Director of Gravitas. Since 2007, Sean has served the school as Academic Dean, History Department Chair, Teacher, Coach, and Dorm Parent. His Ethics Bowl team has won the Long Island Regional Competition four years in a row. He has won several teaching awards, including the PLATO K-12 Teaching Award, a national award for pre-college philosophy teachers. During the summer of 2021, he will help lead a National Endowment for the Humanities Summer Seminar for teachers entitled "Disputatio and the Pursuit of Wisdom in the Humanities." Additionally, he has been a frequent presenter at conferences and has published several articles on philosophy and education. Sean holds a BA/MA in philosophy from Penn State University, and a Ph.D in philosophy from Baylor University. He loves competitive sports, travel, wildlife photography, architecture, and designing elegant solutions to complex human problems. He lives on the campus of The Stony Brook School with his wife, Emily, and his four children.

Ali Schwein

Alexandra Schwein
Mathematics and Computer Science Faculty

BA in Mathematics, University of Colorado at Boulder

Ali Schwein serves as a math, physics, and computer science teacher for Gravitas. Ali graduated with distinction from the University of Colorado in 2020 with a BA in Mathematics and an Education License. While at CU, Ali earned the Jack Hodges Award for Excellence in Mathematics, she started and led a Bible study for athletes, and won an NCAA title in triathlon. Since graduating she has been working as a teacher and track coach in Boulder, CO. Ali is passionate about building relationships with students, integrating cross curriculum problems into mathematics, and teaching students to find innovative solutions using computer coding. She’s on the hunt for the best vanilla latte, loves spending time with her family and dog, Penny, enjoys accruing plants and succulents, and competes competitively in triathlons.

Michael Webster

Michael Webster
Director of Strategic Partnerships
Mathematics Faculty

M.Ed in Secondary Education - Mathematics, University of Pennsylvania
BA in Mathematics, CUNY Brooklyn College

Michael Webster is a Stony Brook School alumnus from the class of 2011. He began teaching for Gravitas in 2023. Prior to joining Gravitas, he served as a 7th-12th grade Mathematics Teacher at Santiago Christian School in the Dominican Republic. Before moving to the D.R., he taught mathematics, led a dorm,coached JV boys basketball, track, and strength and conditioning, served as a Learning Specialist, and as a Faculty Advisor at The Hill School, a prestigious boarding school in Pottstown, Pennsylvania. One of Michael's career accomplishments is winning a Teaching Innovation Award. He is married to Natalie Webster, also SBS Alum class of 2011. They live in Santiago, Dominican Republic with their three young children and are also fostering a 17 year-old Dominican girl. Mr. Webster loves to eat and cook good food, talk about education, theology, or philosophy, and going to the gym.
Vanessia Wilkins

Vanessia Wilkins
Assistant Director
History Faculty

Ph.D in progress in Curriculum and Instruction, University of Albany
MA in History, Western Kentucky University
BA in History and Spanish, University of North Florida

Vanessia Wilkins serves as the World History Teacher for Gravitas. Vanessia holds a BA in Spanish and a BA in History from the University of North Florida, a MA in History from Western Kentucky University and a MS in Curriculum Development and Instructional Technology from the University at Albany. Currently, she is a doctoral student at UAlbany pursuing a Ph.D in Curriculum and Instruction. She has been privileged to partner with students and teachers in a variety of settings ranging from K-12 to higher education. She has worked as a GED Instructor, History, ELA, and Writing Teacher, Academic Advisor, Career Coach, and Adjunct Professor. Her goal is to create academically engaging learning experiences through an environment that fosters creativity, collaboration, and kindness. With that as her focus, Vanessia serves as part of The Freedom Dreaming for Educational Justice Collective which is directly targeted to changing inequitable schooling systems. Additionally, she shares her passion for student success as an adjunct professor at University of the People. Her teaching philosophy is built on the premise of creating productive members of society through socio economic awareness and educational success as “Lifelong Learners”. Above all, her greatest accomplishment is her family. She lives in Connecticut with her husband, Jonathan, and their four children.