34-03 Francis Lewis Blvd,

Flushing, NY 11358

Tel: 917-563-7380

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Head Muay Thai Coach / Elm Community Charter School After-school Supervisor: Youyung Cho is the founder and head coach of Cornerstone Thai Boxing. As a competitor, Youyung has been training and competing in the sport of Muay Thai for over 10 years. He has amassed over 20 fights and competed against some of the best and toughest athletes in North & South America.
In 2016 Youyung decided to take his passion for Muay Thai and share his knowledge with the community where he grew up, in Queens, NY and Cornerstone Thai Boxing was established. With the help of his partners and team of caring instructors, Cornerstone Thai Boxing has become an acclaimed martial arts school in New York City in a short amount of time, producing multiple Regional Muay Thai title holders in the process. Cornerstone Thai Boxing believes in mentoring and nurturing the future leaders of tomorrow.
Senior Muay Thai Instructor: Justin Choe has been training Muay Thai for the past 6 years under Youyung Cho. He is still an active fighter and as a coach wants to pass his passion for Muay Thai to others.
Muay Thai Instructor / Elm Community Charter School After-school Coordinator: 
Kurt Griemsmann has trained under the Square Circle Muay Thai, Miletech Fighting System and American Top Team and has trained and taught at some of the best Martial Arts schools in New York.
Kurt is also a Certified Personal Trainer through the National Council for Certified Personal Trainers.
As per Kurt: "I love teaching and seeing my students progress and achieve their goals."
Kids Muay Thai Instructor:
Stephanie Darbouze has been training under Cornerstone Thai Boxing for three years. She has two years worth of experience working with children as a school aid for JHS 194 and is currently studying nursing with the goal of becoming a pediatric nurse. 

As per Stephanie: “I take pride in the work I do here at Cornerstone. It brings me great joy to see with each passing day a tremendous amount of growth in the children I teach, not just in physical strength but also in discipline.”

Brazilian Jiu-Jitsu Instrutor (Kids & Adults)  
As a martial arts practitioner since 2002...Coach James Kiang has cross trained in different disciplines and has competed in amateur MMA and Brazilian Jiu-Jitsu...Through constant and dedicated training he has earned coach\instructor level rankings in different martial arts and as well ranks in other disciplines as well...     
Queens College City University of New York -Bachelor of Arts 
American Council on Exercise -Certified Personal Trainer 
Brazilian Jiu Jitsu- Marcelo Garcia- Brown Belt III Combat
Submission Wrestling - Erik Paulson- Coach Level 1  
Inosanto International Martial Arts Instructors Association
-Associate Instructor- (Lee) Jun Fan Gung Fu (Jeet Kune Do)  
-Associate Instructor-The Filipino Martial Arts  
Thai Boxing AssociationAssociate Instructor-Thai Boxing  
Francis Fong Wing Chun AssociationApprentice Instructor Level 1- Wing Chun Kung Fu
TaeKwonDo Instructor: Uni Ha, Black Belt under Eagle Taekwondo Master Park.
As a competitor, she has been ranked number 6th in the world in Junior Competition.
Muay Thai Instructor: Caleb Kim (Bio Coming Soon)