Charles Bibilos, founder

Charles Bibilos is one of the world’s most accomplished independent GMAT instructors, with more than 15 years of experience as a classroom teacher and private tutor.

Charles has worked professionally as a teacher since 1999, and began focusing primarily on the GMAT while working for a major test-prep firm in 2002. Since 2003, Charles has tutored independently in San Francisco, Washington D.C., New York City, and Denver, and he has worked with online GMAT and GRE test-takers in more than 35 countries.

Charles graduated with distinction from Stanford University, and earned a perfect score of 800 (51Q/51V/6.0 AWA) on the GMAT in July 2011. Charles is a master test-taker with an M.A. in Education, and he has earned perfect scores on the ACT, the math SAT, and the GRE. Charles prides himself on being a versatile, charismatic, and empathic teacher, and specializes in assisting students who have struggled to achieve results through mass-market GMAT test-prep courses or GMAT self-study programs.

In conjunction with his efforts to help students with standardized testing, Charles has also developed a deep understanding of college and MBA admissions processes, and has worked with hundreds of students on their MBA application essays, interview skills, and resumes. He has helped applicants gain admission to nearly every elite MBA program, including Stanford, Harvard, Wharton, Columbia, Booth, INSEAD, Cornell, Kellogg, and MIT Sloan, among many others.

In addition to his efforts as a GRE and GMAT tutor, Charles is an accomplished writer who has published two full-length TOEFL books, and he has contributed to economics, art history, ESL, and ornithology textbooks as a writer and editor. Charles is a former professional dancer, and he has worked or studied in South Korea, Russia, Chile, Mexico, and Ecuador. In his spare time, Charles loves to travel, write, exercise, ski, hike, make his infant daughter giggle, argue about economics, and eat massive quantities of international food.

Michael Maietta

The proud owner of a 99th percentile score on the GMAT, Michael graduated summa cum laude in Mechanical Engineering, and is an experienced teacher, writer, and management consultant.

Michael first began to develop his passion for teaching and tutoring at Boston University, where he graduated at the top of his class in Mechanical Engineering. After interrupting his tutoring career with several successful years at a major management consulting firm, Michael rekindled his love for teaching in 2015, and joined GMAT Ninja in 2016. Online reviews of his tutoring can be found here, here, and here.

Michael is the son of two lifelong educators, and he excels at helping students build both their underlying skills and their confidence with the GMAT. Michael strikes a masterful balance between being a genuinely nice guy and being a brutally honest tutor: he’ll always tell you what you need to hear about your GMAT progress – even if it’s not necessarily what you want to hear. And despite his quantitative academic training, Michael excels as one of GMAT Club’s resident GMAT verbal experts; if you enjoyed a GMAT Ninja article or QOTD explanation on the forum, odds are good that Michael wrote it.

Outside of his career as a tutor, Michael is an avid traveler who has visited 19 countries. He has worked in Chile and in Colombia, where he experienced a torrid love affair with ajiaco, obleas, and empanadas. Michael also enjoys surfing, snowboarding, hiking, cycling, and recording his own guitar music.

Dave Goldstein

Dave has taught test prep since 2004, winning teacher-of-the-year awards from two large prep companies before joining GMAT Ninja.

Dave is the ultimate academic Swiss army knife: he graduated magna cum laude with a concentration in Finance from the Wharton School and earned an MFA in Creative Writing from Emerson College, and he also earned 99th percentile scores on both the GMAT and GRE. Dave’s diverse academic pursuits have helped him hone his two most indispensable traits as a teacher: patience and empathy.

While helping his students achieve success on standardized tests has always been deeply rewarding, Dave particularly prizes the lasting relationships he builds with his students. Over the years, Dave’s students have been admitted to Stanford, HBS, MIT, Kellogg, Tuck, and other top programs. A handful of these students have even accepted his open invitation to enjoy a celebratory dinner with his family, post-MBA. (Apparently, the more children Dave has, the less palatable this invitation becomes.)

When Dave isn’t teaching, he’s either enjoying time with his wife and two young daughters, writing, or feeling guilty about the fact that he’s not writing. His fiction and essays have appeared in McSweeney’s, Tablet, The Antigonish Review, and Punchnel’s, among other publications. He recently completed a novel and is in the nerve-wracking early stages of seeking representation for it. (If you know a good literary agent, let us know!) In his seven minutes of daily spare time, Dave enjoys reading very long books, watching basketball, and making creative egg-based dishes for his family.