Our Staff

All primary teachers at St. Mark’s are trained and certified by Association Montessori Internationale (AMI), which is the highest and most authentic Montessori training available. In addition, the entire school staff regularly attend training and workshops in order to offer your child the finest possible educational experience, true to Dr. Montessori’s philosophy and standards. St. Mark’s has a very low rate of staff turnover, which provides a consistent environment for your child.

Miss Kathy Flynn, Director/Teacher received her AMI Primary Diploma from the Washington Montessori Institute in 1975. She has a BA Degree from Ohio Dominican College in Columbus, Ohio. Miss Flynn has been teaching at St. Mark’s since 1979, and became Director in 2009.

Mrs. Kathy Dinnison, Teacher, received her AMI Primary Diploma from the Washington Montessori Institute and a Master’s in Education degree from Loyola University in Maryland in 2006. She has a BA Degree from the University of Pittsburgh, Johnstown, PA. Mrs. Dinnison is a member of AMI/USA and NAMTA( North American Montessori Teachers Association). She has been teaching at St. Mark’s since 2006.

Mrs. Lien Lo, Teacher, received her AMI Primary Diploma from the Washington Montessori Institute and a Master’s in Education degree from Loyola University of Maryland in 2006. She also holds a Master’s in Fine Arts degree from the University of New Orleans. Mrs. Lo is a member of AMI/USA and NAMTA (North American Montessori Teachers Association). She has been teaching at St. Mark’s since 2009.

Mrs. Angela Santelices is the Before and After Care (BAC) Supervisor. Originally from Bolivia, Mrs. Santelices has an Associate’s Degree in Early Childhood Development. She worked as a classroom assistant for 7 years at St. Mark’s, as well as the the lead teacher in another day care facility, before returning to St. Mark’s as the BAC Supervisor in 2015.

Mrs. Ana Pilson is Miss Flynn’s assistant. Mrs.Pilson worked as a teacher’s assistant in Angola for seven years, and at child development centers in Alexandria, VA, before joining St. Mark’s in 2012.

Mrs. Tzighie Deri is Mrs. Dinnison’s assistant. She had extensive experience working with children in a day care in Eritrea before moving to Fairfax County. She joined St. Mark’s in 2003, and earned the AMI Montessori Assistant’s certificate in 2008.

Mrs. Isabelle Tran is Mrs. Lo’s assistant. Originally from France, Mrs. Tran worked as an assistant in a preschool in Alexandria. She taught french elementary before joining  St. Mark’s in 2004. Mrs. Tran earned the AMI Montessori Assistant’s certificate in 2008.

Mrs. Reylani Gajudo is the Before and After Care Assistant. She is originally from the Philippines, where she was working towards a BS Degree in Education. She gained experience working in schools in Fairfax County before joining St. Mark’s in 2009.

Mrs. Deirdre O’Donoghue is the Administrative Assistant for St. Mark’s Montessori School. She is originally from Ireland. She had many years of corporate work experience, as well as some child care experience, before joining us at St. Mark’s in 2012.

Mrs. Deena Mackert is our permanent substitute. Mrs. Mackert worked as the Before Care Supervisor for 17 years before retiring, and now helps out as needed in a substitute or support role.