http://www.independencedayball.com/

This is the link to a Dance Camp held in Washington DC. It doesn't specifically say anything about kids classes, but at 14 you should have no trouble handling classes with adults. They have wonderful instructors set to teach this year. Igor and Polina Pilipenchuk, Victor Fung, Karina Smirnoff. You can also sign up for private instruction if you like. I do know they filled up last year, so if you are interested, try to register early.