Abdelghani Bellaachia, Ph.D.

Stemtree Education Center is the brainchild and passion of our founder, Abdelghani “Bell” Bellaachia.  Affectionately known as “Dr. Bell,” he is a familiar face at Stemtree and can often be found mentoring staff, working with students, or chatting with parents.

Bell’s love of – and knack for – the study of science, technology, engineering, and math (STEM) inspired his own path as both a student and an educator.  In addition to earning degrees of his own in Electrical Engineering (BA, MS), Computer Science (MS), and Software Systems (Ph.D.), Bell has over 25 years of experience teaching at the college level.  He also served as an Associate Professor at his alma mater, George Washington University.

His teaching, as well his vast experience in research and professional positions within the scientific community, have opened his eyes to the importance of a rigorous and robust education in STEM.  This understanding has fostered in him an unwavering commitment to preparing tomorrow’s leaders for their future careers.

In 2008, Bell became a Mathnasium franchisee – opening the first one, followed by a second and third center in Northern Virginia. Bell was one of the top franchisees for five years in a row (2010-2015). But Bell’s ultimate dream was to establish his own science and engineering education center – with its own curriculum, its own character, and its own charm.

Thus was born Stemtree Education Center.

Bell’s sights are set on creating in Stemtree a premiere center for the science, technology, and engineering for children in grades K-12.

Michelle Kang

Michelle has been with Stemtree since the inception.  She promotes and markets our programs to local elementary schools and their PTAs.  She also manages our after-school programs and serves as a communications manager for special events.

Michelle brings 16+ years of executive experience in financial services (commercial banks, trust companies, and employee benefits consulting firms).  She is an active volunteer in her community holding leadership positions in PTAs.

Prior to joining Stremtree, Michelle was with Mathnasium as an after-school math instructor and manager responsible for all after school programs in Vienna area.

Michelle holds a B.S. degree in Finance from Syracuse University.


Suneeta Rana

Suneeta Rana attended Fairfax County Public Schools and received her B.S. in Information Systems from George Mason University. She spent 17 years in the IT field in Government/DoD/Intelligence and the private sector in Silicon Valley as a Programmer, Network Administrator, Program Manager, Instructor and Technical Trainer. She started working as a Database Applications Programmer at a local computer company at age 16 and then went on to design and implement several computer systems for the Fairfax County Fire & Rescue, U.S. Air Force, and the Environmental Protection Agency. She was a self-taught Certified Network Administrator. She automated Fairfax County’s Emergency Medical Service Incident Report.

Suneeta developed & installed an EPA system in regional offices across America. As a Program Manager, she received the National Performance Review Award from former Vice President Al Gore for creating the 1st website for the CIA.

She taught an Associate’s Degree class in Network Engineering Management at Computer Learning Center in San Jose. As a Technical Trainer in Silicon Valley, she travelled around the world teaching UNIX and Computer Hardware classes.

She is Secretary of the Westbriar Elementary PTA and started Odyssey of the Mind there in 2013. Her youngest daughter is a student at Westbriar and Stemtree and her older daughter, a graduate of Fairfax County Public Schools, is majoring in Business Information Technology at Virginia Tech.

Suneeta is passionate about getting kids excited about STEM at an early age, especially girls!

Humera Khan

Humera Khan is an Engineer by profession and has worked as a bioengineering research assistant in the Orthopedics department at NYU Hospital for Joint Diseases (HJD) for 3 years. She earned her BE in Electrical Engineering from Stony Brook University in 2010 and MS in Biomedical Engineering from NYU Polytechnic School of Engineering in 2014. During her years at NYU HJD, she worked on different projects which were published in reputed journals.

In addition, she has a passion to teach children in STEM subjects and has tutored undergraduates in core courses  such as  Mathematics and Physics. To further excel and advance in her career, she keeps herself busy by learning new softwares and making use of online education to further sharpen her skills. Along these lines, she recently completed an online training course for Statistical Analysis Software (SAS).

Currently, she lives with her husband in Ashburn, VA and they are looking forward to welcoming their first baby.

Krystyna Larkham

Krystyna’s main driving passion is helping people to increase their level of scientific understanding, so they can better understand the world around them and make informed decisions about everything from their health to the environment.

She holds an MA in Natural Science from the University of Cambridge and an MSc in Environmental Technology from Imperial College, London, in the United Kingdom. She has over five years’ experience tutoring Biology and Chemistry to AP level, and also taught in a private high school for two years where she was responsible for the Biology and Personal, Social, Health and Economic (PSHE) programs.


Krystyna has also worked in Romania and Slovakia in Europe on community programs for mining and petrochemical projects, supporting community members to understand technical reports relating to their safety. A recent arrival to the USA, she enjoys exploring Northern Virginia with her husband, and volunteering at the Arlington Food Assistance Center (AFAC), participating in cooking and nutrition workshops for elementary and high school students.

Chrystal Oden

Hi! My name is Chrystal Oden and I am a graduate of Cornell University. Though I have a particular interest in Ecology and Evolutionary Biology, I received my BS with a general concentration in Biology from the College of Agriculture and Life Sciences.

I gained so much knowledge during my time at Cornell, and, though I always knew I loved learning, I discovered that I enjoyed sharing that knowledge with others, both young and old, equally as much. As a zookeeper and animal caretaker volunteer throughout undergrad, I was actively involved in public education and enjoyed teaching school groups and camps about topics ranging from anatomy to conservation biology. Working at Stemtree has further cultivated this passion and inspired me to continue instilling this curiosity for learning in the minds of our young, eager students.

Aside from hiking to class in subzero temperatures, my experience at Cornell included participating in intramural and club sports and volunteering with numerous organizations from the Cayuga Nature Center to Habitat for Humanity. I was a puppy sitter for Guiding Eyes for the Blind at Cornell and 2 year president of the women’s club basketball team. Currently, I am a volunteer at Hamilton Volunteer Rescue Squad in western Loudoun and plan to continue my education with a Bachelor of Science in Nursing over the coming years.

Jeffery Warner

My name is Jeffery Warner, I am a graduate of George Mason University. I have a Bachelor of Science in Biology. I have always loved teaching and tutoring. While attending George Mason I tutored at the university level in biology, chemistry, organic chemistry, anatomy and physiology.

After graduating, I was hired on as an adjunct professor at George Mason University teaching Ecology & Evolution, and Anatomy & Physiology labs. In addition to this I have worked with high school and middle school students for years through private tutoring, and coaching high school cross country and track during my freshman and sophomore year in college. I started working at Stemtree in the fall of 2014, and love being a part of the Stemtree family. I have always had a passion for teaching and helping kids reach their goals.

My favorite thing to see when tutoring a student is that eureka moment where their eyes light up as they finally get what they have been working so hard on.

Sid Rajesh

Hi I’m Sid Rajesh. I’ve always enjoyed tutoring. I’ve tutored a variety of subjects ranging from Computer Science to Biology. Previously, I taught a group of elementary school students about the Chesapeake Bay and its ecosystem. I’ve been a member of the Stemtree team since 2014.  It’s always enjoyable to see students have fun while learning.

I’m currently finishing my computer science degree at George Mason University. I plan on starting my Masters in Computer Science soon after finishing my undergraduate degree. When I’m not studying, I enjoy travelling and watching movies.


Alexander Krikorian

Alex Krikorian wants to live in a world where everyone has the chance to learn about computers and robotics. As a tutor, he’s been helping kids explore technology and engineering concepts at Stemtree. Alex is pursuing his computer science degree at George Mason University, and when he’s not tutoring, you can find him on the computer, furthering his knowledge about technology. Discover how your child can explore the world of STEM at Stemtree.