Indie Contractors yes...if you get 1099 from the leagues/schools/associations you work. I believe the amount earned of $600 or more from one will land you a 1099 in which you must report it and if that's the case, see if your tax person will include stuff I list below...
My tax lady writes off my mileage, expenses related to uniform (shoes, shirts, pants, knee brace
). I'm guessing travel expenses could be included but I've never gone far enough that an overnight or meals were necessary for me to report.