You do not typically have the right to sign up your son for something during ex-wife's time unless you specifically have a court order that you can do so, or you have sole legal custody. You have to get her prior approval. Otherwise, she can choose not to bring him. Unless something else is going on, you probably don't have a change of circumstances that would be necessary to file for a modification of custody.
Answered on Apr 17th, 2013 at 8:57 PM