For some reason or other, teenagers gravitate toward activities where other teens are either involved as participants or as spectators. After a few years of excellent karate training, kids who formally wouldn't be considered football/basketball/etc material are now able to make "the team". When faced with the decision to remain in karate with it's low key recognition factor or join the high school "team" with all the "benefits", few opt to remain in the dojo.
This trend will change when the dojo gets involved with the school system to accept karate and tournaments as recognized phys-ed programs and when dojo can somehow get the schools to run the tournaments.
This will involve dojo working together and of course, this will be the toughest challenge of all.
"Do or do not. there is no try!"