Our Team


Math Tutors



  • Dr. Chao Xie

    SAT Math/Algebra/Calculus/AP Statistics

    Dr. Chao Xie majored in Math for both her Bachelor and Master degrees. She earned a Ph.D. degree in Measurement and Statistics. She has strong content knowledge in Algebra, Geometry, Pre-Calculus, Calculus I, and Calculus II. She has given group lectures on different advanced topics on math and statistics at the graduate and high school levels. She tutored individual students as well. Dr. Xie enjoys teaching. With strong expertise in both math content and psychometrics, she knows how to use assessment data to facilitate students’ learning via testing.



  • Hana Yu

    PSAT/SAT/ACT Math, AP Calculus, AP Statistics

    Hana Yu is a business administration student at the University of Michigan Ross School of Business, with concentrations in strategy and finance. Graduating from Thomas Jefferson High School for Science and Technology in 2019, she has a strong quantitative foundation in STEM, receiving perfect scores in SAT I, SAT II, and ACT mathematics and 5s on AP Calculus and AP Statistics exams. She enjoys teaching and has participated in volunteer programs dedicated to helping students with math and reading skills, and she has experience in both classroom and one-on-one settings.


  • Reading and Writing Tutors



  • Dr. Romina da Costa

    SAT EBRW-Evidence-Based Reading and Writing/SAT Essay Writing

    Dr. Romina da Costa graduated from Yale University and holds a Masters (Harvard) and a PhD (University Maryland, College Park) in the field of international education. She has taught reading and writing courses to high school and college students since 2007, including academic and analytical writing and writing for the SAT. In her free time, Romina enjoys bike rides, cooking and yoga.



  • Theresa Bennett

    SAT EBRW-Evidence-Based Reading and Writing

    Theresa Bennett is the Director of Assessment for the Delaware Department of Education.  She has 28 years of experience in education as a teacher, instructional coach, trainer and state leader.  Mrs. Bennett currently supervises the administration of the Delaware State Assessment System of which the SAT is the state’s high school accountability assessment; she works regularly with College Board on resources to support students, parents and teachers.  Prior to supervising the state assessment system, Mrs. Bennett was the state lead for English/Language Arts and was instrumental in preparing secondary teachers to support students taking the SAT.  Prior to working at the State Department, Mrs. Bennett was a literacy coach working hands-on with teachers on the instruction of reading and writing at the secondary level.  Mrs. Bennett is an adjunct instructor for Wilmington University, with over 12 years of experience, preparing service and preservice teachers in methods of teaching reading, writing, and becoming literacy specialists.  Mrs. Bennett is the recipient of the Delaware Literacy Association’s Jean Martin Award for her dedication to promoting literacy for students in Delaware.


  • Management Team



  • Dr. Liru Zhang

    Senior Strategic Officer

    Dr. Zhang earned her PhD from University of Iowa specialized in measurement and statistics. Starting as a psychometrician at ACT and continuing as a psychometrician for state assessment programs, she has full experience in designing and developing state assessments, and adopting SAT to serve state assessment needs. Dr. Zhang is working as a senior strategic officer, supervising and providing consultancy to the strategic decisions of the products.



  • Dr. Rosalyn Bryant

    Assessment and Learning Strategist

    Dr. Bryant earned her PhD from University of Maryland and specializes in the assessment and evaluation of instructor and learner processes. She has over 20 years of experience defining, developing, delivering, measuring, and monitoring educational interventions and experiences within a variety of creative in-person and remote learning situations. Moreover, Dr. Bryant holds secondary teacher and school administrator certification credentials.