Meet Our Team

Dr. Allen Grabo

Owner, Verbal Instructor


Allen is a psychologist and mentor who recognizes the value of both words and numbers. With an MSc and PhD in Social & Organizational Psychology, he has presented cross-disciplinary psychological research and findings at scientific conferences in more than 10 countries, publishing 6 scientific articles in peer-reviewed journals with over 400 citations and 10,000 reads.

His passion for language tutoring goes back to 2006, when he relocated to Madrid to teach English as a Second Language. During his time there he worked with private students, prestigious universities like Villanueva, and Fortune 500 corporations such as Philips, Accenture, and Dell. Over the course of his graduate studies at VU University Amsterdam, he supervised over 100 bachelor's and master's theses in psychology, leadership, and human resource management.

Today, Allen is the proud owner and verbal tutor at Breakthrough Test Prep, carrying on the 35-year legacy of founder Harriet Broder in the Potomac area. His dedication to excellence is reflected in the consistent 5-star ratings across platforms like Google, Yelp, Thumbtack, and Tutors.com.

At Breakthrough Test Prep, Allen offers personalized one-on-one sessions with students from some of the nation's most prestigious schools, helping them set and surpass their own ambitious academic goals.

Harriet Broder

Founder, Verbal Instructor


Harriet is well known in the Washington DC area for significantly boosting students' test scores, and has over three decades of experience with students of all levels - from from an Ivy League-bound former President's daughter to the struggling student with weak critical reading skills.

Harriet Broder has been dedicated to the field of verbal standardized test preparation on a full-time basis since 1978, and established her first test prep company, Studyworks, with a colleague in 1982. The company quickly gained popularity and became the top local provider of test prep services, catering to both groups and individual students. As the company continued to grow, Harriet would go on to found her own company, hiring and training additional tutors to meet the increasing demand in the Montgomery County area.

In 2009, Harriet enrolled in the Institute for Integrative Nutrition in 2009 to pursue her second passion - health and alternative medicine. Much of what she learned there enhanced her test preparation programs, including techniques for mindset, foods for focus and concentration, and tools to address test anxiety.

She has authored a book on test prep (6 Secrets To Mastering SAT & ACT Test Taking) and continues to teach and work as a consultant - developing the curriculum and materials that help students at Breakthrough's Test Prep programs succeed.

Harriet spends her off hours cooking (simple) recipes as well as entertaining her adorable tortie cat, Tootsie - Breakthrough’s only official greeter!

Charles Upton

Math Instructor


Charles has been a dedicated educator for over 19 years, with a focus on standardized test preparation. He spent 8 years working at a tutoring center in Bethesda, where he rose to head of math curriculum before coming into his own as an associate with Breakthrough.

Charles's approach to test prep combines his positive attitude, creativity, and intelligence, and he has a proven track record of success. He has a natural ability to connect with students of all backgrounds and create an environment that fosters growth and learning.

Charles loves using a Socratic approach to teaching, guiding his students to arrive at conclusions on their own through questioning and discussion. He believes that this approach not only helps students retain information better but also empowers them to be more confident and independent learners. He is passionate about helping students develop critical thinking skills and a love for learning, and he is dedicated to providing a supportive and challenging environment for students to reach their full potential.