Directory

After a distinguished career in the military, which included stints as a cannon crewman, a military intelligence officer and several tours in Iraq and Afghanistan, Reyno Arredondo ’87 returned to his alma mater in 2017 as head wrestling coach. He earned his Bachelor of Science degree from the United States Military Academy at West Point and a Master of Arts degree from the University of Texas at Austin. During his military career he taught in the Department of Foreign Languages and Behavioral Sciences and Leadership, as well as serving as an associate athletic director in the Directorate of College Athletics, Army-West Point. At St. Mark’s he is also a physical education teacher for Middle and Upper School students, seventh grade baseball coach, seventh grade adviser and sponsors the Martial Arts Club. He’s an inductee in the Texas Wrestling Hall of Honor and was awarded three Bronze Stars and earned Airborne and Air Assault wings during his military service.

A 1995 graduate of St. Mark’s, William Atkinson ’95 joined the faculty as a Humanities teacher before being appointed Head of Upper School. A participant in the Pecos Wilderness program, he is also an assistant varsity football football coach and assists with assorted Middle School sports. He holds bachelor’s and master’s degrees from Southern Methodist University. After graduating from St. Mark’s, Atkinson attended West Point for two years before pursuing a career in law enforcement, teaching situational awareness to elite military personnel around the world. An accomplished artist, his work is exhibited in professional art galleries on the east and west coasts and Europe.

Having joined the faculty in 2020, Gregory Bergeron is a member of the Mathematics Department, where he teaches classes in mathematics to seventh graders. He’s a seventh grade adviser and coaches eighth grade volleyball. Bergeron holds a bachelor’s degree from the University of Louisiana-Monroe and a master’s degree in counseling from Amberton University. Prior to joining St. Marks, Bergeron taught for 30 years, including two years in the Ouachita Parish School System in Louisiana, nine years in the Little Cypress-Mauriceville school district in Orange and the last 19 years in the Highland Park ISD. During his time at HPHS, Bergeron taught high school math, coached the women’s soccer team and the Academic Decathlon team.

A member of the Marksman Wellness Center team, Dr. Mary Bonsu began her St. Mark’s career in 2020 and currently serves as psychologist and Upper School counselor. She earned a Bachelor of Arts degree from Southern Methodist University and both master’s and doctoral degrees from Regent University. Before coming to St. Mark’s, Dr. Bonsu worked as a pediatric psychologist at Children’s Health. She serves as an adviser in the 11th-12th grade class rotation and sponsors the Mindful4Life Club.

Before joining St. Mark’s, Bryan Boucher taught and coached for 14 years in several public schools in Connecticut, Georgia and Texas. A member of the History and Social Sciences Department, he teaches classes in AP U.S. history and AP microeconomics, and is co-sponsor in the junior and senior class advisory rotations. After receiving his bachelor’s degree from Connecticut College, he completed a two year fellowship program with the United States Golf Association before beginning his career as an educator. With a master’s degree from the University of North Texas, he has been awarded the Ackerman Character Education Award at St. Mark’s in 2021 and was recognized as an “Outstanding Educator” from the University of Chicago, based on student recommendations. Boucher has served as an AP reader for various subjects since 2011 and previously worked as an AP regional consultant.

Ryan Brewer began his St. Mark’s career in 2020 and currently serves as biology and life science teacher as a member of the Science Department. Brewer earned his bachelor’s degree from Morehouse College and a master’s degree in education from the University of North Florida. Before joining St. Mark’s, he taught biology at The Bolles School in Jacksonville, FL and also served as a basketball coach and a member of the residential life staff. Brewer serves as an Upper School class sponsor and coaches JV basketball and Middle School football.

David Brown joined the St. Mark’s faculty in 1999. He earned his Bachelor of Arts degree from Oral Roberts University, a Master of Arts degree from San Diego State University and an MFA from Pennsylvania State University. Before joining St. Mark’s, Brown taught English and served as language arts coordinator for grades 1-12 in the Highland Park Independent School District. After teaching English and serving as the Victor F. White Master Teaching Chair in English, Brown stepped away from the classroom to become the School's first Director of Character & Leadership Education. Additionally, he continues to serve as Director of the St. Mark's Literary Festival. Brown received the Ralph B. Rogers Alumni Award in 2020 and was the Marksmen yearbook dedicatee in 2012. He has twice delivered the Baccalaureate faculty address.

Dr. Lauren Brozovich began her St. Mark’s career in 2021 and currently teaches courses in AP English language, freshman English and AP English. Brozovich earned her A.B. from Harvard College, and A.M. and Ph.D. degrees from Harvard University. Before joining St. Mark’s, Dr. Brozovich taught English at Deerfield Academy and Phillips Academy. She also was a tenure-track professor of English at The University of Houston where she taught both undergraduate and graduate courses on American literature, poetry and ecocriticism. Dr. Brozovich serves as faculty co-sponsor of The Marque and the Advanced Poetry Analysis Club. At Phillips Academy, Brozovich received the Elizabeth Rogers Teaching Fellowship and at Harvard University, she received the Thomas Temple Hoopes Prize for Excellence in the Art of Teaching and a Harvard University Certificate of Distinction in Teaching. For her Ph.D. studies, she received an Andrew W. Mellon Fellowship in humanistic studies from the Woodrow Wilson Foundation.

Natalie Bumpas has been a member of the School’s athletics staff since 2020 and currently serves as athletic trainer. She earned a bachelor’s degree from Indiana University and a Master of Arts degree from the University of Iowa. Before coming here, Bumpas served as an associate athletic trainer at Northwestern University and as an assistant athletic trainer at the University of Nebraska-Omaha. She also interned for the New York Mets during the 2011 season. Bumpas is nationally certified by the National Athletic Trainers’ Association (NATA) Board of Certification, and has been a member of NATA since 2004. She is also a licensed athletic trainer in the state of Texas and recently became certified in Graston Technique for soft tissue mobilization.

A member of the College Counseling team since 2020, Phoebe Butler is associate director of College Counseling. Butler earned her bachelor’s degree from New York University, an M.A. degree from Columbia University and an M.P.A. from New York University. Before joining St. Mark’s, she worked in undergraduate admissions at NYU and Pace University. Butler serves as a ninth-grade adviser and sponsors the Public Speaking Club. She holds membership in the National Association for College Admission Counseling, the Texas Association for College Admission Counseling and thenAssociation of College Counselors in Independent Schools.

Alli Carroll joined St. Mark’s in 2022 and currently serves as school nurse. Carroll earned her B.A. from Southern Methodist University and a bachelor of science degree from New York University. Before joining St. Mark’s, she worked for Children’s Health and Texas Children’s Hospital. Prior to entering the nursing profession, Carroll had a career in public relations.

Appointed as the department chair in 2013, Fletcher Carron holds the Stephen M. Seay ‘68 Science Department chair position. He earned a bachelor’s degree in mechanical engineering from Rice University and teaches Upper School and eighth grade students in the field of physical science (physics and chemistry). He began his St. Mark’s career in 2002 and coaches seventh grade basketball, sponsors the Upper School Robotics Team and has served as Pecos Wilderness Trip group leader. A dad to Fletcher Carron ‘32, he is an advisor in the junior-senior advisory rotation. Carron received the John H. Murrell Excellence in Teaching Award in 2008 and was named the Texas Middle School Coach of the Year in 2019-2020.

Dr. CJ (Chia-Jung) Chiang serves as the president of the Chinese Language Teachers Association of Texas (2022-2024) and is a board member of National Taiwan Normal University Heritage Foundation of North America. She joined the St. Mark’s faculty as a member of the Language Department in 2017, where she teaches classes in Chinese. A St. Mark’s parent (Eli Lin ‘28), she earned her bachelor’s and master’s degrees from National Taiwan Normal University and her doctorate from the University of Texas at Austin. Chiang taught at St. Michael’s Catholic Academy, Fusion Academy, Austin ISD schools and in Taiwan. She serves as a seventh-grade advisor and sponsors the Upper School Yoyo Club and the Middle School Chinese Club.

Coming to the School in 2018, Sarah Choi is a member of the Fine Arts faculty and serves as orchestra director. Choi attended The Juilliard School, Yale University’s School of Music and Boston University’s College of Fine Arts. She is a former faculty member at New England Conservatory’s Preparatory School and the San Francisco Conservatory’s Pre-College Division. Choi has performed with numerous Bay Area orchestras, as a Nashville recording studio musician and the Dallas Opera Orchestra. She is a sixth grade adviser and sponsors the Upper School’s Music for Eternity Club.

A recipient of both the John H. Murrell Excellence in Teaching Award (2014) and the Ralph B. Rogers Award (2019), David Cox began his St. Mark’s career in 2009, and currently serves as Latin and classics teacher in the Language Department. Cox earned a Bachelor of Arts degree from Brown University and Master of Arts degree from the University of Virginia. Before joining St. Mark’s, he taught Latin and English at The Middlesex School in Concord, MA, and Latin, Greek, English and history at The Potomac School in McLean, VA. He supervises the Sodalitas Classica Sancti Marci (The Classics Club) in both the Upper and Middle School divisions. He was a classics honors major, a Phi Beta Kappa member and winner of the Lucius Lyons Prize for excellence in Latin and Greek at Brown University. His son, Jordan, is a member of the class of 2018.

After two decades as a sports journalist with the Houston Chronicle and The Athletic (a New York Times publication), Jenny Creech began her St. Mark’s career in 2022. Here she teaches courses in beginning journalism, advanced journalism (newspaper production) and graphic editing and design (yearbook production). She advises The ReMarker newspaper, the Marksmen yearbook, Focus magazine and the online edition of The ReMarker, smremarker.com. A graduate of the University of Oklahoma, she holds a master’s degree from Columbia University.

Coming to St. Mark’s in 2022, Anna Crouch is senior associate director of Admission and Financial Aid. She earned a bachelor’s degree from Dickinson College. Prior to joining the School, Crouch was director of Admission at Mercersburg Academy, a college preparatory boarding school. At Mercersburg, she served as dorm parent, class dean, advisor and yoga teacher alongside her admission duties for 11 years. Previously, Crouch worked at a boutique public relations firm specializing in crisis management in Washington, D.C. She serves as a seventh grade adviser.

A member of the Office of Development and Alumni Relations, Tim Crouch joined the School in 2021 and serves as director of Development. Crouch earned his bachelor’s degree from Dickinson College and a master’s of business administration from the University of Maryland. Previously at Mercersburg Academy, a college preparatory boarding school, he served as a faculty member, adviser, head boys basketball coach and director of Leadership Giving there.

Julie Doerge joined the St. Mark’s faculty in 2006 and is the school nurse. Doerge earned her A.D. from Ferris State University and is a registered nurse (RN). She previously worked ten years at the Hockaday School, six years at the Kingwood School and worked six years overseas in England and Switzerland. Doerge spent two summers working at the Dallas Health and Human Services with Dr. Wendy Chung. She is a member of the National Association of School Nurses and the Texas School Nurse Association. Doerge received both the Ralph B. Rogers Alumni Award and the Marksmen yearbook dedication in 2022.

Returning to his alma mater, Dr. Zachary Erwin ’96 serves as chair of the Language Department, a position he has held since 2018. He teaches classes in Spanish and earned a bachelor’s degree from Emory University. He holds master’s and doctoral degrees from Duke University. Prior to St. Mark’s, Erwin taught Spanish language at Swarthmore College, the University of Texas at Austin and Monmouth College. He sponsors the Sociedad Honoraria Hispánica Spanish Honor Society and is a member of the American Association of Teachers of Spanish and Portuguese and the American Council on the Teaching of Foreign Language.

David Evans joined the St. Mark’s faculty in 2006 as a member of the Language Department, where he teaches Spanish to Middle and Upper School students. He earned a Bachelor of Arts degree from Brigham Young University and a master’s degree in Spanish Peninsular Literature from Brigham Young University. Before coming to St. Mark’s, Evans was a graduate assistant at Brigham Young University. Evans coaches volleyball, serves as an eighth-grade advisor and is a regular participant in the Wilderness Program as a leader of the eighth-grade campout and the Pecos Wilderness trip. In 2023, he received the John H. Murrell Excellence in Teaching Award and is a member of the American Association of Teachers of Spanish and Portuguese. He’s the dad to Grant ‘23.

David Fisher came to St. Mark’s in 2016 as chair of the History and Social Sciences Department after a more than 25-year career on the international school circuit. Prior to coming here, he taught in Malaysia, Argentina, the Phillipines, Oman and Bangladesh. He holds a master’s degree from the University of Cambridge and a bachelor’s degree from Harvard University. Fisher, whose son Nathaniel graduated from here in 2023, has previously worked as an academic dean, department head and college counselor.

After playing football at Princeton University, Harry Flaherty spent brief stints with the New Orleans Saints, Tampa Bay Buccaneers and Dallas Cowboys before moving to the University of Tennessee, where he earned a law degree while coaching football in a graduate assistant role for the Volunteers’ football program. Coming to St. Mark’s in 2021, he now serves as head football coach, Upper School history teacher and adviser in the 11th and 12th grade rotations. Before joining St. Mark’s, Flaherty spent six years at The Lawrenceville School in New Jersey, where he served as a history teacher, head varsity football coach, assistant dean of Admission and housemaster for all ninth grade boarding boys.

Coming to St. Mark’s from Queens, N.Y. where she taught for over a decade, Sherry George joined the St. Mark’s faculty in 2020. A member of the Mathematics Department, she teaches courses in precalculus and calculus to Upper School students. George earned a Bachelor of Arts degree in mathematics and comparative literature from Binghamton University, NY; and a Master of Arts in secondary mathematics education from City College of New York.

Dr. Andrea Hamilton has been a member of the St. Mark’s community since 2019 and is a faculty member in the Department of History and Social Sciences. She teaches courses in history of American society, foundations of world societies and AP U.S. history. A mom to Miller Wendorf ‘24, she earned a doctorate from Tulane University and holds undergraduate degrees from Indiana University and Southern Methodist University. Prior to St. Mark’s she taught a variety of history and English classes at Southern Methodist University. Hamilton sponsors the St. Mark’s chapter of Junior World Affairs Council and travels with the School’s Model United Nations team.

Cameron Hillier ’13 returned to his alma mater in 2020 as a member of the English Department, where he teaches classes in junior English, literature of war and survival and dystopian literature. Before returning to St. Mark’s, he earned a bachelor’s degree from Colby College. Hillier is the head tennis coach here, directs the School’s Wilderness Program and serves as an adviser in the freshman-sophomore class rotation. He also taught English at Christ School in Asheville, NC while coaching tennis and serving as head of house for one of the campus dormitories there.

Matt Hjertstedt has been a member of the St. Mark’s community since 2008 and serves as head athletic trainer in the Athletic Department, where he also teaches Middle School physical education and health classes. He earned his Bachelor of Science degree from Central Washington University and Master of Science degree from Texas Tech University Health Sciences Center. He’s also a certified athletic trainer and a licensed athletic trainer. Before joining St. Mark’s, Hjertstedt worked in the fitness industry as a personal trainer and strength coach. A dad to current Marksman Westin ‘31, he also spent time working at Harborview Medical Center in Seattle in the Acute Rehab Unit. Hjertstedt also sponsors an independent studies course in sports medicine for Upper School students and received the John H. Murrell Excellence in Teaching Award in 2014.

Ken Howell started his St. Mark’s career in 2023 as a member of the Mathematics Department, where he teaches courses in algebra and precalculus to students in the Upper School. He earned a Bachelor of Science degree from Lees McRae College and a master’s degree in teaching mathematics from University of Texas at Dallas. Before coming to St. Mark’s, Howell taught mathematics at Jesuit Preparatory School where he was an assistant coach for the varsity lacrosse team and the head coach for the bowling team.

A member of the Science Department faculty, Wesley Irons joined St. Mark’s in 2021 and currently teaches physics to Upper School students. He holds a bachelor’s degree from the University of Texas at Austin and is an avid movie buff and historian. He worked for six years at the Oakridge School in Arlington, where he taught all levels of physics and calculus. Irons is an adviser in the junior-senior class rotation and has participated as an AP reader three times.

Dr. Michael Lane joined the St. Mark’s faculty in 2023 as holder of the Leonard N. “Doc” Nelson Alumni Master Teaching Chair. Lane earned his bachelor’s degree and Ph.D. from the University of California-Berkeley. Before joining St. Mark’s, Lane worked for 24 years at the College Preparatory School in Oakland, CA, teaching physics, chemistry, astronomy and neuroscience, and coaching a variety of sports. Besides teaching Middle School science classes, Lane is the director of the Winn Science Center Planetarium. In 1991, Lane was the winner of the American Chemical Society (Division of Nuclear Chemistry and Technology) Charles D. Coryell Award in nuclear chemistry.

A native of Taiwan, Janet Lin holds the Gene and Alice Oltrogge Master Teaching Chair and teaches courses in Chinese. She earned her bachelor’s degree in journalism from the Universal Journalism College and a bachelor’s degree in philosophy from the Soochow University in Taipei, Taiwan. Before joining St. Mark’s, Lin taught Mandarin Chinese at an International Baccalaureate school and served as an IB examiner. Before joining the education field, Lin was a journalist, working at a television station, newspaper and magazine. Lin serves on the junior-senior class advisory rotation and sponsors the Chinese Club and the Chinese Honor Society. A Cum Laude faculty member, she also serves on the School’s Discipline Council and is co-sponsor of International Week. She received the John H. Murrell Excellence in Teaching Award in 2019.

Dr. Daniel Lipin is a member of the Science Department where he teaches courses in biology to Upper School students. Lipin, who came to St. Mark’s in 2022, earned his bachelor’s degree and master’s degree from the University of Manchester and a doctorate from University of Australia, Brisbane. Before he arrived at St. Mark’s, Lipin taught chemistry, biology, earth science, physics and astronomy at the Hackley School in Tarrytown, N.Y. A dad to Marksman Ron Drori-Lipin ’31, he also has more than ten years of experience coaching Lego robotics. He co-directs the Lower and Middle School Robotics Program and also sponsors the Scientific Marksmen magazine and the Middle School Lego Club. Upon completion of his Ph.D., Lipin won the Dean’s Award for Outstanding Higher Degree by Research Theses (2010). While teaching at the Hackley School, he earned the Mary Lambos Award for excellence in teaching (2013) and the McLean Chair in Mathematics and Science (2020-2022).

After being drafted by the National Football League and playing with the Dallas Cowboys and the San Diego Chargers, Sean Lissemore joined the St. Mark’s administrative team as athletic director in 2019. He earned his bachelor’s degree from the College of William and Mary and his master’s degree from Indiana University. A former collegiate football player at the College of William and Mary, he served as team captain and earned All-American honors. He was drafted into the NFL where he played for seven years, including three with the Dallas Cowboys. Sean founded and organized the Sean Lissemore Youth Football Camp, a free enrichment program for children in Dumont, N.J. and was named the San Diego Charger’s NFL Military Salute to Service nominee. Sean is a member of the National Interscholastic Athletic Administrators Association and is a Certified Athletic Administrator. He also serves as eighth grade class adviser.

Nancy Marmion came to St. Mark’s in 1985 from The Hockaday School, where she taught Spanish. She served as chair of the Language Department from 1994 to 2018. Marmion currently holds the J.J. Connolly Master Teaching Chair, as well as serving as the faculty chair of the Discipline Council, Spanish Club sponsor and co-sponsor of International Week. She earned her A.B. from the College of William and Mary and M.A. from the University of Texas at Austin. She received the John H. Murrell Excellence in Teaching Award in 1989. Marmion is a member of American Council on the Teaching of Foreign Languages (ACTFL) and the American Association of Teachers of Spanish and Portuguese (AATSP). In 2018, she received the Life-Long Service Award from the Lone Star Chapter of the AATSP.

Paul Mlakar is the director of Academic Information Systems and a member of the Mathematics Department, where he teaches AP calculus courses to junior and senior students. Beginning his St. Mark’s career in 2003, he also serves as scheduler for Upper and Middle Schools and coaches the Upper School Academic Quiz Bowl team. He earned a Master of Education degree in curriculum and instruction from the University of Houston after earning a Bachelor of Science degree in mathematics education from The Ohio State University. Mlakar has worked in various aspects of education throughout his career, first as a high school math teacher in Pasadena, TX followed by an education specialist position at the Space Center in Houston, the visitor center for NASA’s Johnson Space Center. He left that position to serve as an education specialist at the Region IV Education Service Center in Houston, where he provided training and professional development to math teachers. He has authored numerous mathematics curricula for geometry, algebra II, and mathematical modeling.

After 15 years at Ursuline Academy of Dallas, where he taught earth science, chemistry and physics, Dr. Jonathan Moody arrived at St. Mark’s as a chemistry teacher in 2021. Moody coaches Middle School cross-country and track & field, is a freshman adviser and participated as a group leader in the Wilderness Program. He earned his B.S. from Texas A&M University and Ph.D. from UT Southwestern Medical Center. Moody has twice received the Work of Heart award from the Catholic Foundation of Dallas, was named a Regional Coach of the Year in 2021 by the Positive Coaching Alliance and was named the 2017 Texas Cross-Country Coach of the Year by the Lone Star Christian Sports Network.

Michael Morris began his St. Mark’s career in 2014 and currently serves as English Department chair. Morris earned his B.A. from Williams College and M.A. from Columbia University. Before joining the St. Mark’s faculty, he taught and led the English Department at Vail Mountain School in Colorado and Western Reserve Academy in Ohio. Morris teaches freshman English and advises students in their junior and senior years. He has engaged in professional development through the National Endowment for the Humanities, the College Board and the Klingenstein Center for Independent School Leadership.

Named one of the best ceramicists by D Magazine, Rachel Muldez came to St. Mark’s in 2022 and is a member of the Fine Arts faculty, teaching courses in wood and metal and 3-D design. She has a bachelor’s degree from Baylor University and two master’s degrees (University of Houston-Clear Lake and University of Dallas). Before coming to St. Mark’s, Muldez taught ceramics at Dallas College-Richland and was also a full-time artist and public speaker. She is a seventh-grade adviser and a co-sponsor of the Nature Conservatory Club. She has had her artwork collected and displayed on several occasions at the National Hispanic Cultural Center Museum. Her work has also been exhibited in many galleries including the gallery located in the governor of New Mexico’s office.

Ken Owens is a 1989 graduate of St. Mark’s and now serves as a chemistry teacher. He earned a B.A. from Rice University and an M.S. from the University of Michigan. Owens previously taught at The Oakridge School in Arlington and worked for the Rice University Police Department, volunteered at Mount Rushmore and ran blood drives. He sponsors the U.S. Department of Energy Science Bowl competition for Upper School students. Owens received the John H. Murrell Excellence in Teaching Award in 2003 and belongs to the National Science Teaching Association, the Associated Chemistry Teachers of Texas, the Science Teachers Association of Texas and the American Geophysical Union.

In his position as director of Civic Responsibility, Dr. John Perryman is a member of both the History and Social Sciences Department and the English Department where he teaches courses in sophomore English, AP history and the highly popular senior elective, “A 100-year partnership: A history of St. Mark’s and the City of Dallas.” He joined the School in 2009 and previously served as assistant head of the Upper School. He earned a bachelor’s degree from Williams College and both a master’s degree and a doctorate from the University of Texas at Dallas. He was the recipient of the Marksmen yearbook dedication in 2016.

Analisa Rodriguez has served as director of bands since joining the faculty in 2022. She earned her B.M. from Trinity University and an M.Mus. from the University of North Texas. Previously, Rodriguez was an assistant band director at Alamo Heights High School in San Antonio. She is a doctoral student working on a Ph.D. in music education at the University of North Texas, where her research topic is “Music Meets Masculinity: An Ethnography of an All-Boys Band Program.”

Mark Scheibmeir joined the St. Mark’s faculty in 2022 as a film studies teacher in the Fine Arts Department. He previously served as an arts educator and coach at OTM Acting Studio in Los Angeles and taught at the University of Texas at Austin. Scheibmeir maintains an active role in the entertainment industry as an actor, writer, director and producer. He sponsors the Film Club and serves as a ninth-grade adviser. He earned B.S. and M.F.A. degrees from the University of Texas at Austin. 

Lynne Weber Schwartz teaches A.P. Literature and Composition (12) and tenth grade English. She has held the Trustee Master Teacher Chair in Humanities for the past 20 years. Lynne sponsors the award-winning literary/art magazine The Marque and is the director of the St. Mark’s Teacher Institute. Before teaching at St. Mark’s, Lynne taught at Highland Park High School and the Mesquite Independent School District. For a number of years, she has served as lead consultant at a multitude of College Board A.P. English summer institutes in the Southwest. For seventeen years, she also served as a senior lecturer at The University of Texas at Dallas, teaching Curriculum and Instruction in English to pre-service teachers. In 2005, Lynne received the College Board’s Special Recognition Award. Lynne was editor-in-chief of the Laying the Foundation series of teacher guides and was the project director for the English Vertical Teams Guide published by the College Board. She holds a B.A. in History from UCLA and a Master of Humanities degree from The University of Dallas. Lynne is married and has a grown son and a daughter in Dallas, as well as a new granddaughter, Scarlett Rose.

Josh Shandera joined St. Mark’s in 2020 as Associate Director of College Counseling. A native of San Antonio, Josh earned his bachelor’s degree from the University of Texas at Austin before joining the UT-Austin Admission staff. During his tenure in UT admissions, Josh has served in a variety of roles, mostly recently as Admissions and Recruitment Coordinator for the Canfield Business

Holder of the Malcolm and Melinda Brachman Master Teaching Chair, Dr. Martin Stegemoeller teaches courses in humanities to eighth graders. He earned a Bachelor of Arts degree from Northwestern University and a master’s degree and doctorate from Vanderbilt University. Before coming to St. Mark’s, Stegemoeller taught English and math, coached golf and tennis, was a dorm parent and did development work at Lake Forest Academy in Illinois. Before that, he was an assistant professor at the University of Alabama in Huntsville. He is the faculty sponsor for the Telos Leadership Society, the Upper School Philosophy Club and the Middle School Philosophy Club. Stegemoeller received the Franklin J. Machette Teaching Award from Vanderbilt University in 1993, the John H. Murrell Excellence in Teaching Award in 2007, and the Ralph B. Rogers Alumni Award in 2013. He has been chosen by the Senior Class to deliver the Baccalaureate address twice and was the Marksmen yearbook dedicatee in 2011.

Mark Sullivan joined the St. Mark's School of Texas faculty in 1982 as the Lower School Physical Education Coordinator. Prior to his appointment as the Director of Athletics and Physical Education in 2000, Mark has served the school as the Wilderness Program Director, the Assistant Head of the Middle School and as a coach and teacher in the Athletic Department. Mark holds a Bachelor of Science Degree and a Masters Degree in Educational Administration from the University of North Texas, and is a recipient of the John H. Murrell Excellence in Teaching Award. Mark's coaching has included numerous Middle School sports as well as the Varsity Volleyball team and the Varsity Diving team.

After a collegiate coaching career at Mary Hardin-Baylor University, Darren Teicher joined the St. Mark’s faculty in 2008 where he serves as head volleyball coach. He earned a bachelor of science degree from the University of Mary Hardin-Baylor, where he won a national championship as a player. As a coach here, his teams have won seven SPC volleyball championships.

Katy Tye began her St. Mark’s career in 2023 and currently serves as Upper and Middle drama teacher. Tye earned a bachelor’s degree in fine arts from Southern Methodist University and a master’s degree in fine arts from Wayne State University. Prior to coming here, Tye co-founded a non-profit theater called Prism Movement Theater, where she wrote and choreographed numerous shows. She has acted and directed in the Dallas area at several theaters including Undermain, Echo, Theatre Three, and Dallas Children’s Theater. In addition to her work in theater, Tye provides motion capture for Gearbox Studios (Borderlands) and has voiced characters for Crunchyroll Studios (One Piece). She is an adviser in the freshman-sophomore rotation and is a member of the Society of American Fight Directors.

Trey Whitty joined the St. Mark’s faculty in 2022 and is the head lacrosse coach. Whitty earned a Bachelor of Arts degree from the University of Virginia. Prior to joining St. Mark’s, Whitty served as the head lacrosse coach and director of athletics at St. Paul’s School in Brooklandville, MD. He has also taught and coached at McDonogh School and St. Mary’s High School in Maryland. Whitty teaches Middle and Upper School physical education, is a 12th grade adviser and the head coach of the eighth grade football team. Whitty is a two-time USA Lacrosse Assistant Coach of the Year recipient.

Katherine Wood serves as Middle and Upper School art teacher. Coming to St. Mark’s in 2019, she earned a B.F.A. from the University of North Texas and an M.A. and M.F.A. from the University of Dallas. Previously, Wood taught at the University of North Texas, the University of Dallas, the University of Texas at Arlington and Mountain View College. She is a sixth grade adviser and Upper School Creative Arts Club sponsor. Wood’s studio practice consists of 2D work that interprets expansive hypothetical spaces, inspired by mathematical theories, physical infrastructure and nature. Her work has been shown at dozens of exhibitions.

As a member of the Upper School office, Leila Wright joined the St. Mark’s staff in 2022 as assistant to the head of Upper School and registrar. She earned a bachelor’s from the University of Texas at Austin. Before joining St. Mark’s, Wright worked at a non-profit focused on providing extracurricular opportunities to students and was part of the Dallas Independent School District’s Teacher Excellence Initiative team. She also taught math in Oak Cliff as part of the Teach for America program. Wright founded Girls Rock Dallas, a summer music program for girls and young women.

Scott Ziegler has been a member of the St. Mark’s community since 2016 where he is a member of the Fine Arts Department, instructing classes in ceramics. He is also assistant director of the Wilderness Program. Ziegler earned bachelor’s and master’s in education degrees from Loyola University and a master’s degree in fine arts from Northern Illinois University. Prior to joining St. Mark’s, he taught at the University of North Carolina, the University of Saint Francis and Barrington High School in Illinois. He earned the John H. Murrell Excellence in Teaching Award in 2021 and is the father of two Marksmen, Logan ‘29 and Grayson ‘31.