Our daughter wanted to join a track camp this summer, so she could improve on her time in track & field. However, once the camp started she started slacking off and only attending the camp (which meets 2x per week) and attends the meets once a week, instead of following the coach's scheduled practice runs, the rest of the week. She has not been improving, although she has been complaining about it, and is slacking off by not practicing.
So in order to "motivate" her and give her choices, I said if she does not follow the coach's practice schedule for the other days, then she would have to walk/jog/run back from her 1/2 day summer camp she was taking instead of me picking her up. (She is 13 and bikes to school, so she knows her way around.) She was so stubborn and said she would rather walk the 4 miles home. I said fine and set the GPS on her phone and said "Good luck and she can call/text me by 12:15 if she changes her mind." (I even texted her at noon to see if she wanted to change her mind but she texted me that she would rather walk.) I made sure my husband was in agreement, in case she called him to ask him to pick her up. She did end up walking home and ever since that day, she has decided to do the coach's practice runs! : )
We gave her a choice and avoided having to nag her about practices and averted a prolong fight over it, as well!
Good job parents! Keep up those choices!