Slow,
I have been part of several youth sports organizations, some were LLC, some were 501, and some were just a loose gathering of hoodlums.....
Based on that experience, I would suggest that if you are serious about the organization, both today and in the future, and can take a long term approach, you should look 501c3. It can be a bit of a pain to get going, depending on circumstances, but that is where I would look first.
Obviously, you have to determine what is gonna help you out in the long run, but if you know what you are shooting for, it can help with your articles of incorporation and charter documents that have to be submitted.
Verbiage plays a huge part in the IRS determination.